Our students have been involved in new and exciting interdisciplinary research and have published in leading high impact journals including Nature Chemistry, Nature Communications, JACS, Angewandte Chemie, Applied Physics Letters, ACS Nano, Nano Letters, Advanced Materials, Nature Protocols, PloS one, and many others.
A full list of the work published by our NanoDTC Students, Associates and others, acknowledging the NanoDTC grants EP/G037221, EP/L015978 and EP/S022953/1 is below. If you want to view the papers on google scholar, see here.
Some papers published by our students are also featured below with some additional contextual information.
Last updated: Mar 2021
Looking inside lithium-ion batteries
Spectroscopy and Electrocatalysis for a Sustainable Future
From waste to fuel: quantifying sustainability
Novel spin states discovered in silicon-based artificial atoms
A step forward in efficient artificial photosynthesis
Self-assembling hydrogels on microfluidic droplets that respond to light or chemical stimuli by disassembling
2016
132.
Tabachnyk, Maxim; Karani, Arfa H; Broch, Katharina; Pazos-Outón, Luis M; Xiao, James; Jellicoe, Tom C; Novák, Jiř'i; Harkin, David; Pearson, Andrew J; Rao, Akshay; others,
Efficient singlet exciton fission in pentacene prepared from a soluble precursor Journal Article
In: APL Materials, vol. 4, no. 11, pp. 116112, 2016.
@article{tabachnyk2016efficient,
title = {Efficient singlet exciton fission in pentacene prepared from a soluble precursor},
author = {Maxim Tabachnyk and Arfa H Karani and Katharina Broch and Luis M Pazos-Outón and James Xiao and Tom C Jellicoe and Ji{ř}{'i} Novák and David Harkin and Andrew J Pearson and Akshay Rao and others},
url = {https://aip.scitation.org/doi/full/10.1063/1.4968518},
year = {2016},
date = {2016-01-01},
journal = {APL Materials},
volume = {4},
number = {11},
pages = {116112},
publisher = {AIP Publishing LLC},
abstract = {Carrier multiplication using singlet exciton fission (SF) to generate a pair of spin-triplet excitons from a single optical excitation has been highlighted as a promising approach to boost the photocurrent in photovoltaics (PVs) thereby allowing PV operation beyond the Shockley-Queisser limit. The applicability of many efficient fission materials, however, is limited due to their poor solubility. For instance, while acene-based organics such as pentacene (Pc) show high SF yields (up to200%), the plain acene backbone renders the organic molecule insoluble in common organic solvents. Previous approaches adding solubilizing side groups such as bis(tri-iso-propylsilylethynyl) to the Pc core resulted in low vertical carrier mobilities due to reduction of the transfer integrals via steric hindrance, which prevented high efficiencies in PVs. Here we show how to achieve good solubility while retaining the advantages of molecular Pc by using a soluble precursor route. The precursor fully converts into molecular Pc through thermal removal of the solubilizing side groups upon annealing above 150 °C in the solid state. The annealed precursor shows small differences in the crystallinity compared to evaporated thin films of Pc, indicating that the Pc adopts the bulk rather than surface polytype. Furthermore, we identify identical SF properties such as sub-100 fs fission time and equally long triplet lifetimes in both samples.},
keywords = {},
pubstate = {published},
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}
Carrier multiplication using singlet exciton fission (SF) to generate a pair of spin-triplet excitons from a single optical excitation has been highlighted as a promising approach to boost the photocurrent in photovoltaics (PVs) thereby allowing PV operation beyond the Shockley-Queisser limit. The applicability of many efficient fission materials, however, is limited due to their poor solubility. For instance, while acene-based organics such as pentacene (Pc) show high SF yields (up to200%), the plain acene backbone renders the organic molecule insoluble in common organic solvents. Previous approaches adding solubilizing side groups such as bis(tri-iso-propylsilylethynyl) to the Pc core resulted in low vertical carrier mobilities due to reduction of the transfer integrals via steric hindrance, which prevented high efficiencies in PVs. Here we show how to achieve good solubility while retaining the advantages of molecular Pc by using a soluble precursor route. The precursor fully converts into molecular Pc through thermal removal of the solubilizing side groups upon annealing above 150 °C in the solid state. The annealed precursor shows small differences in the crystallinity compared to evaporated thin films of Pc, indicating that the Pc adopts the bulk rather than surface polytype. Furthermore, we identify identical SF properties such as sub-100 fs fission time and equally long triplet lifetimes in both samples.
131.
Bergholt, Mads S; St-Pierre, Jean-Philippe; Offeddu, Giovanni S; Parmar, Paresh A; Albro, Michael B; Puetzer, Jennifer L; Oyen, Michelle L; Stevens, Molly M
Raman spectroscopy reveals new insights into the zonal organization of native and tissue-engineered articular cartilage Journal Article
In: ACS central science, vol. 2, no. 12, pp. 885–895, 2016.
@article{bergholt2016raman,
title = {Raman spectroscopy reveals new insights into the zonal organization of native and tissue-engineered articular cartilage},
author = {Mads S Bergholt and Jean-Philippe St-Pierre and Giovanni S Offeddu and Paresh A Parmar and Michael B Albro and Jennifer L Puetzer and Michelle L Oyen and Molly M Stevens},
url = {https://pubs.acs.org/doi/abs/10.1021/acscentsci.6b00222},
year = {2016},
date = {2016-01-01},
journal = {ACS central science},
volume = {2},
number = {12},
pages = {885--895},
publisher = {American Chemical Society},
abstract = {Tissue architecture is intimately linked with its functions, and loss of tissue organization is often associated with pathologies. The intricate depth-dependent extracellular matrix (ECM) arrangement in articular cartilage is critical to its biomechanical functions. In this study, we developed a Raman spectroscopic imaging approach to gain new insight into the depth-dependent arrangement of native and tissue-engineered articular cartilage using bovine tissues and cells. Our results revealed previously unreported tissue complexity into at least six zones above the tidemark based on a principal component analysis and k-means clustering analysis of the distribution and orientation of the main ECM components. Correlation of nanoindentation and Raman spectroscopic data suggested that the biomechanics across the tissue depth are influenced by ECM microstructure rather than composition. Further, Raman spectroscopy together with multivariate analysis revealed changes in the collagen, glycosaminoglycan, and water distributions in tissue-engineered constructs over time. These changes were assessed using simple metrics that promise to instruct efforts toward the regeneration of a broad range of tissues with native zonal complexity and functional performance.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Tissue architecture is intimately linked with its functions, and loss of tissue organization is often associated with pathologies. The intricate depth-dependent extracellular matrix (ECM) arrangement in articular cartilage is critical to its biomechanical functions. In this study, we developed a Raman spectroscopic imaging approach to gain new insight into the depth-dependent arrangement of native and tissue-engineered articular cartilage using bovine tissues and cells. Our results revealed previously unreported tissue complexity into at least six zones above the tidemark based on a principal component analysis and k-means clustering analysis of the distribution and orientation of the main ECM components. Correlation of nanoindentation and Raman spectroscopic data suggested that the biomechanics across the tissue depth are influenced by ECM microstructure rather than composition. Further, Raman spectroscopy together with multivariate analysis revealed changes in the collagen, glycosaminoglycan, and water distributions in tissue-engineered constructs over time. These changes were assessed using simple metrics that promise to instruct efforts toward the regeneration of a broad range of tissues with native zonal complexity and functional performance.
130.
Richter, Johannes M; Abdi-Jalebi, Mojtaba; Sadhanala, Aditya; Tabachnyk, Maxim; Rivett, Jasmine PH; Pazos-Outón, Luis M; Gödel, Karl C; Price, Michael; Deschler, Felix; Friend, Richard H
Enhancing photoluminescence yields in lead halide perovskites by photon recycling and light out-coupling Journal Article
In: Nature communications, vol. 7, no. 1, pp. 1–8, 2016.
@article{richter2016enhancing,
title = {Enhancing photoluminescence yields in lead halide perovskites by photon recycling and light out-coupling},
author = {Johannes M Richter and Mojtaba Abdi-Jalebi and Aditya Sadhanala and Maxim Tabachnyk and Jasmine PH Rivett and Luis M Pazos-Outón and Karl C Gödel and Michael Price and Felix Deschler and Richard H Friend},
url = {https://www.nature.com/articles/ncomms13941?origin=ppub},
year = {2016},
date = {2016-01-01},
journal = {Nature communications},
volume = {7},
number = {1},
pages = {1--8},
publisher = {Nature Publishing Group},
abstract = {In lead halide perovskite solar cells, there is at least one recycling event of electron–hole pair to photon to electron–hole pair at open circuit under solar illumination. This can lead to a significant reduction in the external photoluminescence yield from the internal yield. Here we show that, for an internal yield of 70%, we measure external yields as low as 15% in planar films, where light out-coupling is inefficient, but observe values as high as 57% in films on textured substrates that enhance out-coupling. We analyse in detail how externally measured rate constants and photoluminescence efficiencies relate to internal recombination processes under photon recycling. For this, we study the photo-excited carrier dynamics and use a rate equation to relate radiative and non-radiative recombination events to measured photoluminescence efficiencies. We conclude that the use of textured active layers has the ability to improve power conversion efficiencies for both LEDs and solar cells.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
In lead halide perovskite solar cells, there is at least one recycling event of electron–hole pair to photon to electron–hole pair at open circuit under solar illumination. This can lead to a significant reduction in the external photoluminescence yield from the internal yield. Here we show that, for an internal yield of 70%, we measure external yields as low as 15% in planar films, where light out-coupling is inefficient, but observe values as high as 57% in films on textured substrates that enhance out-coupling. We analyse in detail how externally measured rate constants and photoluminescence efficiencies relate to internal recombination processes under photon recycling. For this, we study the photo-excited carrier dynamics and use a rate equation to relate radiative and non-radiative recombination events to measured photoluminescence efficiencies. We conclude that the use of textured active layers has the ability to improve power conversion efficiencies for both LEDs and solar cells.
129.
Jellicoe, Tom C; Richter, Johannes M; Glass, Hugh FJ; Tabachnyk, Maxim; Brady, Ryan; Dutton, Siân E; Rao, Akshay; Friend, Richard H; Credgington, Dan; Greenham, Neil C; others,
Research data supporting "Synthesis and Optical Properties of Lead-Free Cesium Tin Halide Perovskite Nanocrystals" Journal Article
In: 2016.
@article{jellicoe2016research,
title = {Research data supporting "Synthesis and Optical Properties of Lead-Free Cesium Tin Halide Perovskite Nanocrystals"},
author = {Tom C Jellicoe and Johannes M Richter and Hugh FJ Glass and Maxim Tabachnyk and Ryan Brady and Siân E Dutton and Akshay Rao and Richard H Friend and Dan Credgington and Neil C Greenham and others},
url = {https://www.repository.cam.ac.uk/handle/1810/254023},
year = {2016},
date = {2016-01-01},
publisher = {University of Cambridge},
abstract = {The uploaded data is the basis for all figures presented in the manuscript and the Supporting Information
This research data supports “Synthesis and Optical Properties of Lead-Free Cesium Tin Halide Perovskite Nanocrystals” which has been published in “Journal of the American Chemical Soceity”.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The uploaded data is the basis for all figures presented in the manuscript and the Supporting Information
This research data supports “Synthesis and Optical Properties of Lead-Free Cesium Tin Halide Perovskite Nanocrystals” which has been published in “Journal of the American Chemical Soceity”.
This research data supports “Synthesis and Optical Properties of Lead-Free Cesium Tin Halide Perovskite Nanocrystals” which has been published in “Journal of the American Chemical Soceity”.
128.
Tait, Edward; Hine, Nicholas
Research data supporting'Simulation of electron energy loss spectra of nanomaterials with linear-scaling density functional theory'. Journal Article
In: 2016.
@article{tait2016research,
title = {Research data supporting'Simulation of electron energy loss spectra of nanomaterials with linear-scaling density functional theory'.},
author = {Edward Tait and Nicholas Hine},
url = {https://aspace.repository.cam.ac.uk/handle/1810/253717},
year = {2016},
date = {2016-01-01},
publisher = {University of Cambridge},
abstract = {Input and output files for the simulations performed for the publication "Simulation of electron energy loss spectra of nanomaterials with linear-scaling density functional theory" Several software packages were used: onetep (linear Scaling DFT) http://www.onetep.org/ castep (conventional plane wave DFT) http://www.castep.org/ ELK (all electron DFT) http://elk.sourceforge.net/ OptaDoS (computing spectra) http://www.optados.org/ Input files for all simulations are included, as are relevant textual and binary outputs. The data to reproduce the experimental lines is not included, but may be extracted from the publications cited in the paper. Viewers may find the .elnes_bin and .odi files of particular interest as these may be used (together with OptaDoS) to compute new EEL spectra for the atoms studied using different broadening parameters or in polarised geometries (i.e. not isotropically averaged).},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Input and output files for the simulations performed for the publication "Simulation of electron energy loss spectra of nanomaterials with linear-scaling density functional theory" Several software packages were used: onetep (linear Scaling DFT) http://www.onetep.org/ castep (conventional plane wave DFT) http://www.castep.org/ ELK (all electron DFT) http://elk.sourceforge.net/ OptaDoS (computing spectra) http://www.optados.org/ Input files for all simulations are included, as are relevant textual and binary outputs. The data to reproduce the experimental lines is not included, but may be extracted from the publications cited in the paper. Viewers may find the .elnes_bin and .odi files of particular interest as these may be used (together with OptaDoS) to compute new EEL spectra for the atoms studied using different broadening parameters or in polarised geometries (i.e. not isotropically averaged).
127.
Young, Laurence J; Ströhl, Florian; Kaminski, Clemens F
A guide to structured illumination TIRF microscopy at high speed with multiple colors Journal Article
In: JoVE (Journal of Visualized Experiments), no. 111, pp. e53988, 2016.
@article{young2016guide,
title = {A guide to structured illumination TIRF microscopy at high speed with multiple colors},
author = {Laurence J Young and Florian Ströhl and Clemens F Kaminski},
url = {https://www.jove.com/t/53988/a-guide-to-structured-illumination-tirf-microscopy-at-high-speed-with},
year = {2016},
date = {2016-01-01},
journal = {JoVE (Journal of Visualized Experiments)},
number = {111},
pages = {e53988},
abstract = {Optical super-resolution imaging with structured illumination microscopy (SIM) is a key technology for the visualization of processes at the molecular level in the chemical and biomedical sciences. Although commercial SIM systems are available, systems that are custom designed in the laboratory can outperform commercial systems, the latter typically designed for ease of use and general purpose applications, both in terms of imaging fidelity and speed. This article presents an in-depth guide to building a SIM system that uses total internal reflection (TIR) illumination and is capable of imaging at up to 10 Hz in three colors at a resolution reaching 100 nm. Due to the combination of SIM and TIRF, the system provides better image contrast than rival technologies. To achieve these specifications, several optical elements are used to enable automated control over the polarization state and spatial structure of the illumination light for all available excitation wavelengths. Full details on hardware implementation and control are given to achieve synchronization between excitation light pattern generation, wavelength, polarization state, and camera control with an emphasis on achieving maximum acquisition frame rate. A step-by-step protocol for system alignment and calibration is presented and the achievable resolution improvement is validated on ideal test samples. The capability for video-rate super-resolution imaging is demonstrated with living cells.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Optical super-resolution imaging with structured illumination microscopy (SIM) is a key technology for the visualization of processes at the molecular level in the chemical and biomedical sciences. Although commercial SIM systems are available, systems that are custom designed in the laboratory can outperform commercial systems, the latter typically designed for ease of use and general purpose applications, both in terms of imaging fidelity and speed. This article presents an in-depth guide to building a SIM system that uses total internal reflection (TIR) illumination and is capable of imaging at up to 10 Hz in three colors at a resolution reaching 100 nm. Due to the combination of SIM and TIRF, the system provides better image contrast than rival technologies. To achieve these specifications, several optical elements are used to enable automated control over the polarization state and spatial structure of the illumination light for all available excitation wavelengths. Full details on hardware implementation and control are given to achieve synchronization between excitation light pattern generation, wavelength, polarization state, and camera control with an emphasis on achieving maximum acquisition frame rate. A step-by-step protocol for system alignment and calibration is presented and the achievable resolution improvement is validated on ideal test samples. The capability for video-rate super-resolution imaging is demonstrated with living cells.
126.
Gross, Manuela A; Creissen, Charles E; Orchard, Katherine L; Reisner, Erwin
Research Data Supporting "Photoelectrochemical hydrogen production in water using a layer-by-layer assembly of a Ru dye and Ni catalyst on NiO" Journal Article
In: 2016.
@article{gross2016research,
title = {Research Data Supporting "Photoelectrochemical hydrogen production in water using a layer-by-layer assembly of a Ru dye and Ni catalyst on NiO"},
author = {Manuela A Gross and Charles E Creissen and Katherine L Orchard and Erwin Reisner},
url = {https://www.repository.cam.ac.uk/handle/1810/255990},
year = {2016},
date = {2016-01-01},
publisher = {University of Cambridge},
abstract = {experimental data for manuscript and supporting information
This research data supports "Photoelectrochemical hydrogen production in water using a layer-by-layer assembly of a Ru dye and Ni catalyst on NiO" which is published in "Chemical Science."},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
experimental data for manuscript and supporting information
This research data supports "Photoelectrochemical hydrogen production in water using a layer-by-layer assembly of a Ru dye and Ni catalyst on NiO" which is published in "Chemical Science."
This research data supports "Photoelectrochemical hydrogen production in water using a layer-by-layer assembly of a Ru dye and Ni catalyst on NiO" which is published in "Chemical Science."
125.
Ouassou, Jabir Ali; Bernardo, Angelo Di; Robinson, Jason WA; Linder, Jacob
Electric control of superconducting transition through a spin-orbit coupled interface Journal Article
In: Scientific reports, vol. 6, no. 1, pp. 1–9, 2016.
@article{ouassou2016electric,
title = {Electric control of superconducting transition through a spin-orbit coupled interface},
author = {Jabir Ali Ouassou and Angelo Di Bernardo and Jason WA Robinson and Jacob Linder},
url = {https://www.nature.com/articles/srep29312},
year = {2016},
date = {2016-01-01},
journal = {Scientific reports},
volume = {6},
number = {1},
pages = {1--9},
publisher = {Nature Publishing Group},
abstract = {We demonstrate theoretically all-electric control of the superconducting transition temperature using a device comprised of a conventional superconductor, a ferromagnetic insulator and semiconducting layers with intrinsic spin-orbit coupling. By using analytical calculations and numerical simulations, we show that the transition temperature of such a device can be controlled by electric gating which alters the ratio of Rashba to Dresselhaus spin-orbit coupling. The results offer a new pathway to control superconductivity in spintronic devices.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
We demonstrate theoretically all-electric control of the superconducting transition temperature using a device comprised of a conventional superconductor, a ferromagnetic insulator and semiconducting layers with intrinsic spin-orbit coupling. By using analytical calculations and numerical simulations, we show that the transition temperature of such a device can be controlled by electric gating which alters the ratio of Rashba to Dresselhaus spin-orbit coupling. The results offer a new pathway to control superconductivity in spintronic devices.
124.
Crespo-Quesada, Micaela; Pazos-Outón, Luis M; Warnan, Julien; Kuehnel, Moritz F; Friend, Richard H; Reisner, Erwin
Metal-encapsulated organolead halide perovskite photocathode for solar-driven hydrogen evolution in water Journal Article
In: Nature communications, vol. 7, no. 1, pp. 1–7, 2016.
@article{crespo2016metal,
title = {Metal-encapsulated organolead halide perovskite photocathode for solar-driven hydrogen evolution in water},
author = {Micaela Crespo-Quesada and Luis M Pazos-Outón and Julien Warnan and Moritz F Kuehnel and Richard H Friend and Erwin Reisner},
url = {https://www.nature.com/articles/ncomms12555},
year = {2016},
date = {2016-01-01},
journal = {Nature communications},
volume = {7},
number = {1},
pages = {1--7},
publisher = {Nature Publishing Group},
abstract = {Lead-halide perovskites have triggered the latest breakthrough in photovoltaic technology. Despite the great promise shown by these materials, their instability towards water even in the presence of low amounts of moisture makes them, a priori, unsuitable for their direct use as light harvesters in aqueous solution for the production of hydrogen through water splitting. Here, we present a simple method that enables their use in photoelectrocatalytic hydrogen evolution while immersed in an aqueous solution. Field’s metal, a fusible InBiSn alloy, is used to efficiently protect the perovskite from water while simultaneously allowing the photogenerated electrons to reach a Pt hydrogen evolution catalyst. A record photocurrent density of −9.8 mA cm−2 at 0 V versus RHE with an onset potential as positive as 0.95±0.03 V versus RHE is obtained. The photoelectrodes show remarkable stability retaining more than 80% of their initial photocurrent for ∼1 h under continuous illumination.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Lead-halide perovskites have triggered the latest breakthrough in photovoltaic technology. Despite the great promise shown by these materials, their instability towards water even in the presence of low amounts of moisture makes them, a priori, unsuitable for their direct use as light harvesters in aqueous solution for the production of hydrogen through water splitting. Here, we present a simple method that enables their use in photoelectrocatalytic hydrogen evolution while immersed in an aqueous solution. Field’s metal, a fusible InBiSn alloy, is used to efficiently protect the perovskite from water while simultaneously allowing the photogenerated electrons to reach a Pt hydrogen evolution catalyst. A record photocurrent density of −9.8 mA cm−2 at 0 V versus RHE with an onset potential as positive as 0.95±0.03 V versus RHE is obtained. The photoelectrodes show remarkable stability retaining more than 80% of their initial photocurrent for ∼1 h under continuous illumination.
123.
Cao, Jing; Massarotti, Davide; Vickers, Mary E; Kursumovic, Ahmed; Bernardo, Angelo Di; Robinson, Jason WA; Tafuri, Francesco; MacManus-Driscoll, Judith L; Blamire, Mark Giffard
Enhanced localized superconductivity in Sr2RuO4 thin film by pulsed laser deposition Journal Article
In: Superconductor Science and Technology, vol. 29, no. 9, pp. 095005, 2016.
@article{cao2016enhanced,
title = {Enhanced localized superconductivity in Sr2RuO4 thin film by pulsed laser deposition},
author = {Jing Cao and Davide Massarotti and Mary E Vickers and Ahmed Kursumovic and Angelo Di Bernardo and Jason WA Robinson and Francesco Tafuri and Judith L MacManus-Driscoll and Mark Giffard Blamire},
url = {https://iopscience.iop.org/article/10.1088/0953-2048/29/9/095005/meta},
year = {2016},
date = {2016-01-01},
journal = {Superconductor Science and Technology},
volume = {29},
number = {9},
pages = {095005},
publisher = {IOP Publishing},
abstract = {Superconducting c-axis-oriented Sr2RuO4 thin film has been fabricated using pulsed laser deposition. Although the superconductivity is localized, the onset critical temperature is enhanced over the bulk value. X-ray microstructural analysis of Sr2RuO4 superconducting and non-superconducting thin films suggests the existence of the localized stacking faults and an overall c-axis lattice expansion which may account for the locally enhanced superconductivity.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Superconducting c-axis-oriented Sr2RuO4 thin film has been fabricated using pulsed laser deposition. Although the superconductivity is localized, the onset critical temperature is enhanced over the bulk value. X-ray microstructural analysis of Sr2RuO4 superconducting and non-superconducting thin films suggests the existence of the localized stacking faults and an overall c-axis lattice expansion which may account for the locally enhanced superconductivity.
122.
Amado, Mario; Li, Yang; Bernardo, Angelo Di; Lombardo, Antonio; Ferrari, Andrea C; Robinson, Jason
Induced magnetism in exfoliated graphene via proximity effect with yttrium iron garnet thin films Proceedings Article
In: APS March Meeting Abstracts, pp. C15–004, 2016.
@inproceedings{amado2016induced,
title = {Induced magnetism in exfoliated graphene via proximity effect with yttrium iron garnet thin films},
author = {Mario Amado and Yang Li and Angelo Di Bernardo and Antonio Lombardo and Andrea C Ferrari and Jason Robinson},
url = {https://ui.adsabs.harvard.edu/abs/2016APS..MARC15004A/abstract},
year = {2016},
date = {2016-01-01},
booktitle = {APS March Meeting Abstracts},
volume = {2016},
pages = {C15--004},
abstract = {The recent discovery of the quantum anomalous Hall effect (QAHE) in magnetically doped topological insulators cooled below in the milikelvin regime represents breakthrough in the field of spintronics. Theoretically, the QAHE should occur in graphene proximity coupled to a ferromagnetic insulato but with the promise of much higher operating temperatures for practical applications. Hints of proximity-induced magnetism in graphene coupled to yttrium iron garnet (YIG) films have been reported although the QAHE remains unobserved; the lack of a fully developed plateau in graphene/YIG devices can be attributed to poor interfacial coupling and therefore a dramatically reduced magnetic proximity effect. Here we report the deposition and characterisation of epitaxial thin-films of YIG on lattice-matched gadolinium gallium garnet substrates by pulsed laser deposition. Pristine exfoliated graphene flakes transferred mechanically onto the YIG are reported alongside results that correlate the effects of YIG morphology on the electronic and crystal properties of graphene by electrical (low temperature magnetoresistance measurements in Hall-bar-like configuration) and optical (Raman) means.},
keywords = {},
pubstate = {published},
tppubtype = {inproceedings}
}
The recent discovery of the quantum anomalous Hall effect (QAHE) in magnetically doped topological insulators cooled below in the milikelvin regime represents breakthrough in the field of spintronics. Theoretically, the QAHE should occur in graphene proximity coupled to a ferromagnetic insulato but with the promise of much higher operating temperatures for practical applications. Hints of proximity-induced magnetism in graphene coupled to yttrium iron garnet (YIG) films have been reported although the QAHE remains unobserved; the lack of a fully developed plateau in graphene/YIG devices can be attributed to poor interfacial coupling and therefore a dramatically reduced magnetic proximity effect. Here we report the deposition and characterisation of epitaxial thin-films of YIG on lattice-matched gadolinium gallium garnet substrates by pulsed laser deposition. Pristine exfoliated graphene flakes transferred mechanically onto the YIG are reported alongside results that correlate the effects of YIG morphology on the electronic and crystal properties of graphene by electrical (low temperature magnetoresistance measurements in Hall-bar-like configuration) and optical (Raman) means.
121.
Keyzer, Evan; Glass, Hugh; Liu, Zigeng; Bayley, Paul M; Dutton, Sian; Grey, Clare; Wright, Dominic
Mg (PF₆) ₂-Based Electrolyte Systems: Understanding Electrolyte-Electrode Interactions for the Development of Mg-Ion Batteries Journal Article
In: 2016.
@article{keyzer2016mgb,
title = {Mg (PF₆) ₂-Based Electrolyte Systems: Understanding Electrolyte-Electrode Interactions for the Development of Mg-Ion Batteries},
author = {Evan Keyzer and Hugh Glass and Zigeng Liu and Paul M Bayley and Sian Dutton and Clare Grey and Dominic Wright},
url = {https://www.repository.cam.ac.uk/handle/1810/263533},
year = {2016},
date = {2016-01-01},
publisher = {American Chemical Society},
abstract = {Mg(PF₆)₂-based electrolytes for Mg-ion batteries have not received the same attention as the analogous LiPF₆-based electrolytes used in most Li-ion cells owing to the perception that the PF₆-anion decomposes on and passivates Mg electrodes. No synthesis of the Mg(PF₆)₂ salt has been reported, nor have its solutions been studied electrochemically. Here, we report the synthesis of the complex Mg(PF₆)₂(CH₃CN)₆ and its solution-state electrochemistry. Solutions of Mg(PF₆)₂(CH₃CN)₆ in CH₃CN and CH₃CN/THF mixtures exhibit high conductivities (up to 28 mS·cm‾¹) and electrochemical stability up to at least 4 V vs Mg on Al electrodes. Contrary to established perceptions, Mg electrodes are observed to remain electrochemically active when cycled in the presence of these Mg(PF₆)₂-based electrolytes, with no fluoride (i.e., MgF₂) formed on the Mg surface. Stainless steel electrodes are found to corrode when cycled in the presence of Mg(PF₆)₂ solutions, but Al electrodes are passivated. The electrolytes have been used in a prototype Mg battery with a Mg anode and Chevrel (Mo₃S₄)-phase cathode.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Mg(PF₆)₂-based electrolytes for Mg-ion batteries have not received the same attention as the analogous LiPF₆-based electrolytes used in most Li-ion cells owing to the perception that the PF₆-anion decomposes on and passivates Mg electrodes. No synthesis of the Mg(PF₆)₂ salt has been reported, nor have its solutions been studied electrochemically. Here, we report the synthesis of the complex Mg(PF₆)₂(CH₃CN)₆ and its solution-state electrochemistry. Solutions of Mg(PF₆)₂(CH₃CN)₆ in CH₃CN and CH₃CN/THF mixtures exhibit high conductivities (up to 28 mS·cm‾¹) and electrochemical stability up to at least 4 V vs Mg on Al electrodes. Contrary to established perceptions, Mg electrodes are observed to remain electrochemically active when cycled in the presence of these Mg(PF₆)₂-based electrolytes, with no fluoride (i.e., MgF₂) formed on the Mg surface. Stainless steel electrodes are found to corrode when cycled in the presence of Mg(PF₆)₂ solutions, but Al electrodes are passivated. The electrolytes have been used in a prototype Mg battery with a Mg anode and Chevrel (Mo₃S₄)-phase cathode.
120.
Offeddu, Giovanni S.; Oyen, Michelle
Smart Nanofibrous Materials for Tissue Engineering Book Section
In: Smart Materials for Tissue Engineering, pp. 401–417, 2016.
@incollection{offeddu2016smart,
title = {Smart Nanofibrous Materials for Tissue Engineering},
author = {Giovanni S. Offeddu and Michelle Oyen},
url = {https://books.google.co.uk/books?hl=en&lr=&id=H3UoDwAAQBAJ&oi=fnd&pg=PA401&dq=info:uLuNbx6DeOcJ:scholar.google.com&ots=8SWQijU482&sig=-DhHLprsY-7hX1Pu-b5Bq6IxzJc&redir_esc=y#v=onepage&q&f=false},
year = {2016},
date = {2016-01-01},
booktitle = {Smart Materials for Tissue Engineering},
pages = {401--417},
abstract = {Nanofibrous tissue engineering scaffolds present cells with a morphology that mimics the natural extra-cellular matrix to aid biocompatibility. The incorporation of smart responses into the scaffolds results in the delivery of stimuli at the scale of single cells, facilitated by the large surface area of the fibrous mesh. The vast range of stimuli provided by polymers fashioned into nanofibers makes it possible to control the chemical and physical signals received by the cells in the scaffold, well after its implantation into the patient's body. Ultimately, this will aid in bridging the gap between research and the clinic, making tissue engineering a viable strategy for the treatment of conditions that are as yet unresolved.},
keywords = {},
pubstate = {published},
tppubtype = {incollection}
}
Nanofibrous tissue engineering scaffolds present cells with a morphology that mimics the natural extra-cellular matrix to aid biocompatibility. The incorporation of smart responses into the scaffolds results in the delivery of stimuli at the scale of single cells, facilitated by the large surface area of the fibrous mesh. The vast range of stimuli provided by polymers fashioned into nanofibers makes it possible to control the chemical and physical signals received by the cells in the scaffold, well after its implantation into the patient's body. Ultimately, this will aid in bridging the gap between research and the clinic, making tissue engineering a viable strategy for the treatment of conditions that are as yet unresolved.
2015
119.
Forse, Alexander C
Nuclear Magnetic Resonance Studies of Ion Adsorption in Supercapacitor Electrodes Journal Article
In: 2015.
@article{Forse2015c,
title = {Nuclear Magnetic Resonance Studies of Ion Adsorption in Supercapacitor Electrodes},
author = {Alexander C Forse},
url = {https://www.repository.cam.ac.uk/handle/1810/278978},
year = {2015},
date = {2015-10-08},
abstract = {Supercapacitors (or electric double-layer capacitors) are high power energy storage devices that store charge by the non-faradaic adsorption of ions at the interface between porous carbon electrodes and an electrolyte solution. The development of new electrode materials and electrolytes with improved performances is an active area of research today, yet there are relatively few studies of the molecular mechanisms of the charge storage process. In this work, nuclear magnetic resonance (NMR) spectroscopy is developed for the study of the charge storage mechanisms of supercapacitors. Importantly, NMR experiments show that electrolyte ions adsorbed inside the pores of the carbon electrodes can be resolved from those in bulk electrolyte for a range of supercapacitor electrode materials. Chemical shift calculations show that the adsorbed species are subject to ring current effects, whereby the delocalised electrons in the carbon shield the nearby nuclei. The calculated effects depend on the local carbon structure, helping to rationalise the variations observed when different porous carbons are studied experimentally, and allowing structural information to be extracted from the spectra. NMR experiments performed on electrodes extracted from ionic liquid-based supercapacitors with different applied voltages allow the numbers of adsorbed ions to be measured upon charging. It is shown that supercapacitor charging involves the migration of both anions and cations in and out of the carbon pores in each electrode, with the anions dominating the charge storage process. When combined with lineshape measurements, which offer information about the diffusion of adsorbed ions, the power performances of supercapacitor devices with different electrolytes are rationalised. In situ NMR methods are then developed to allow mechanistic studies of working supercapacitors as they are charged and discharged inside the NMR magnet. The experiments reveal that the charge storage mechanism depends on both the electrolyte and the electrode material studied. During charging, reversible chemical shift changes are also observed, arising from the introduction of paratropic ring currents. Finally, cross polarisation experiments allow the selective observation of the adsorbed electrolyte species, and show that their motion slows down during supercapacitor charging. Overall, the NMR approach offers unique insights into the molecular mechanisms of the supercapacitance phenomenon.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Supercapacitors (or electric double-layer capacitors) are high power energy storage devices that store charge by the non-faradaic adsorption of ions at the interface between porous carbon electrodes and an electrolyte solution. The development of new electrode materials and electrolytes with improved performances is an active area of research today, yet there are relatively few studies of the molecular mechanisms of the charge storage process. In this work, nuclear magnetic resonance (NMR) spectroscopy is developed for the study of the charge storage mechanisms of supercapacitors. Importantly, NMR experiments show that electrolyte ions adsorbed inside the pores of the carbon electrodes can be resolved from those in bulk electrolyte for a range of supercapacitor electrode materials. Chemical shift calculations show that the adsorbed species are subject to ring current effects, whereby the delocalised electrons in the carbon shield the nearby nuclei. The calculated effects depend on the local carbon structure, helping to rationalise the variations observed when different porous carbons are studied experimentally, and allowing structural information to be extracted from the spectra. NMR experiments performed on electrodes extracted from ionic liquid-based supercapacitors with different applied voltages allow the numbers of adsorbed ions to be measured upon charging. It is shown that supercapacitor charging involves the migration of both anions and cations in and out of the carbon pores in each electrode, with the anions dominating the charge storage process. When combined with lineshape measurements, which offer information about the diffusion of adsorbed ions, the power performances of supercapacitor devices with different electrolytes are rationalised. In situ NMR methods are then developed to allow mechanistic studies of working supercapacitors as they are charged and discharged inside the NMR magnet. The experiments reveal that the charge storage mechanism depends on both the electrolyte and the electrode material studied. During charging, reversible chemical shift changes are also observed, arising from the introduction of paratropic ring currents. Finally, cross polarisation experiments allow the selective observation of the adsorbed electrolyte species, and show that their motion slows down during supercapacitor charging. Overall, the NMR approach offers unique insights into the molecular mechanisms of the supercapacitance phenomenon.
118.
Böhm, Marcus L; Jellicoe, Tom C; Tabachnyk, Maxim; Davis, Nathaniel JLK; Wisnivesky-Rocca-Rivarola, Florencia; Ducati, Caterina; Ehrler, Bruno; Bakulin, Artem A; Greenham, Neil C
Research data supporting "Lead Telluride Quantum Dot Solar Cells Displaying External Quantum Efficiencies Exceeding 120%" Journal Article
In: 2015.
@article{bohm2015research,
title = {Research data supporting "Lead Telluride Quantum Dot Solar Cells Displaying External Quantum Efficiencies Exceeding 120%"},
author = {Marcus L Böhm and Tom C Jellicoe and Maxim Tabachnyk and Nathaniel JLK Davis and Florencia Wisnivesky-Rocca-Rivarola and Caterina Ducati and Bruno Ehrler and Artem A Bakulin and Neil C Greenham},
url = {https://www.repository.cam.ac.uk/handle/1810/252376},
year = {2015},
date = {2015-01-01},
publisher = {University of Cambridge},
abstract = {The data is the basis for all Figures in the manuscript and Supporting Information.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The data is the basis for all Figures in the manuscript and Supporting Information.
117.
Swanson, Jacob J; Boies, Adam; others,
Unsteady bipolar diffusion charging in aerosol neutralisers: a non-dimensional approach to predict charge distribution equilibrium behaviour Journal Article
In: 2015.
@article{swanson2015unsteady,
title = {Unsteady bipolar diffusion charging in aerosol neutralisers: a non-dimensional approach to predict charge distribution equilibrium behaviour},
author = {Jacob J Swanson and Adam Boies and others},
url = {https://www.sciencedirect.com/science/article/pii/S0021850215000440},
year = {2015},
date = {2015-01-01},
publisher = {Elsevier},
abstract = {High total particle concentration and small particle size are common features of aerosols encountered in the field of aerosol-based nanotechnology that can potentially lead to non-equilibrium issues in the neutraliser upon SMPS characterisation, resulting in large errors in size distribution measurements. Experiments show that the commonly assumed product rule fails to predict equilibrium behaviour in aerosol neutralisers under these conditions, as it does not capture the influence of total particle concentration and particle size. The aim of this work is to provide an equilibrium indicator that identifies situations where equilibrium is not reached in the neutraliser as a function of residence time, ion generation rate, total particle concentration, and particle size. Bipolar diffusion charging equations are solved numerically in a one-dimensional model first, and a non-dimensional analysis of the results is carried out in order to map equilibrium behaviour as a function of two non-dimensional groups, the non-dimensional ion concentration, and the non-dimensional neutraliser residence time. Solving the three-dimensional form of the charging equations in the geometry of the neutraliser then enables one to find good agreement in terms of equilibrium behaviour between experiments and predictions from the non-dimensional model. The three-dimensional model captures the complexity of the physics of unsteady particle charging inside a neutraliser. This work then discusses this as a new approach to non-equilibrium behaviour prediction in neutralisers, providing a tool supplementing the product rule that can be used in practice.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
High total particle concentration and small particle size are common features of aerosols encountered in the field of aerosol-based nanotechnology that can potentially lead to non-equilibrium issues in the neutraliser upon SMPS characterisation, resulting in large errors in size distribution measurements. Experiments show that the commonly assumed product rule fails to predict equilibrium behaviour in aerosol neutralisers under these conditions, as it does not capture the influence of total particle concentration and particle size. The aim of this work is to provide an equilibrium indicator that identifies situations where equilibrium is not reached in the neutraliser as a function of residence time, ion generation rate, total particle concentration, and particle size. Bipolar diffusion charging equations are solved numerically in a one-dimensional model first, and a non-dimensional analysis of the results is carried out in order to map equilibrium behaviour as a function of two non-dimensional groups, the non-dimensional ion concentration, and the non-dimensional neutraliser residence time. Solving the three-dimensional form of the charging equations in the geometry of the neutraliser then enables one to find good agreement in terms of equilibrium behaviour between experiments and predictions from the non-dimensional model. The three-dimensional model captures the complexity of the physics of unsteady particle charging inside a neutraliser. This work then discusses this as a new approach to non-equilibrium behaviour prediction in neutralisers, providing a tool supplementing the product rule that can be used in practice.
116.
Michaelis, FB; Salmon, Andrew; Hofmann, Stephan; Baumberg, Jeremy; others,
Controlling nanowire growth by light Journal Article
In: 2015.
@article{michaelis2015controlling,
title = {Controlling nanowire growth by light},
author = {FB Michaelis and Andrew Salmon and Stephan Hofmann and Jeremy Baumberg and others},
url = {https://pubs.acs.org/doi/abs/10.1021/acs.nanolett.5b02953},
year = {2015},
date = {2015-01-01},
publisher = {American Chemical Society},
abstract = {Individual Au catalyst nanoparticles are used for selective laser-induced chemical vapor deposition of single germanium nanowires. Dark-field scattering reveals in real time the optical signatures of all key constituent growth processes. Growth is initially triggered by plasmonic absorption in the Au catalyst, while once nucleated the growing Ge nanowire supports magnetic and electric resonances that then dominate the laser interactions. This spectroscopic understanding allows real-time laser feedback that is crucial toward realizing the full potential of controlling nanomaterial growth by light.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Individual Au catalyst nanoparticles are used for selective laser-induced chemical vapor deposition of single germanium nanowires. Dark-field scattering reveals in real time the optical signatures of all key constituent growth processes. Growth is initially triggered by plasmonic absorption in the Au catalyst, while once nucleated the growing Ge nanowire supports magnetic and electric resonances that then dominate the laser interactions. This spectroscopic understanding allows real-time laser feedback that is crucial toward realizing the full potential of controlling nanomaterial growth by light.
115.
Ying Gu Simon Diesch, Jeffrey Linder; others,
Signature of magnetic-dependent gapless odd frequency states at superconductor/ferromagnet interfaces Journal Article
In: 2015.
@article{diesch2015signature,
title = {Signature of magnetic-dependent gapless odd frequency states at superconductor/ferromagnet interfaces},
author = {Simon Diesch, Ying Gu, Jeffrey Linder, Giorgio Divitini, Caterina Ducati, Elke Scheer, MG Blamire, Jason WA Robinson, and others
},
url = {https://www.nature.com/articles/ncomms9053},
year = {2015},
date = {2015-01-01},
publisher = {Nature Publishing Group},
abstract = {The theory of superconductivity developed by Bardeen, Cooper and Schrieffer (BCS) explains the stabilization of electron pairs into a spin-singlet, even frequency, state by the formation of an energy gap within which the density of states is zero. At a superconductor interface with an inhomogeneous ferromagnet, a gapless odd frequency superconducting state is predicted, in which the Cooper pairs are in a spin-triplet state. Although indirect evidence for such a state has been obtained, the gap structure and pairing symmetry have not so far been determined. Here we report scanning tunnelling spectroscopy of Nb superconducting films proximity coupled to epitaxial Ho. These measurements reveal pronounced changes to the Nb subgap superconducting density of states on driving the Ho through a metamagnetic transition from a helical antiferromagnetic to a homogeneous ferromagnetic state for which a BCS-like gap is recovered. The results prove odd frequency spin-triplet superconductivity at superconductor/inhomogeneous magnet interfaces.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The theory of superconductivity developed by Bardeen, Cooper and Schrieffer (BCS) explains the stabilization of electron pairs into a spin-singlet, even frequency, state by the formation of an energy gap within which the density of states is zero. At a superconductor interface with an inhomogeneous ferromagnet, a gapless odd frequency superconducting state is predicted, in which the Cooper pairs are in a spin-triplet state. Although indirect evidence for such a state has been obtained, the gap structure and pairing symmetry have not so far been determined. Here we report scanning tunnelling spectroscopy of Nb superconducting films proximity coupled to epitaxial Ho. These measurements reveal pronounced changes to the Nb subgap superconducting density of states on driving the Ho through a metamagnetic transition from a helical antiferromagnetic to a homogeneous ferromagnetic state for which a BCS-like gap is recovered. The results prove odd frequency spin-triplet superconductivity at superconductor/inhomogeneous magnet interfaces.
114.
Linder J. Y. Gu, Divitini G.; Diesch, S
Signature of magnetic-dependent gapless odd frequency states at superconductor/ferromagnet interfaces Journal Article
In: Nat. Commun, vol. 6, pp. 8053, 2015.
@article{di2015gu,
title = {Signature of magnetic-dependent gapless odd frequency states at superconductor/ferromagnet interfaces },
author = {Y. Gu, Linder J., Divitini G., Ducati C., Scheer E., Blamire MG & Robinson JWA, A Di Bernardo and S Diesch},
url = {https://www.nature.com/articles/ncomms9053},
year = {2015},
date = {2015-01-01},
journal = {Nat. Commun},
volume = {6},
pages = {8053},
abstract = {The theory of superconductivity developed by Bardeen, Cooper and Schrieffer (BCS) explains the stabilization of electron pairs into a spin-singlet, even frequency, state by the formation of an energy gap within which the density of states is zero. At a superconductor interface with an inhomogeneous ferromagnet, a gapless odd frequency superconducting state is predicted, in which the Cooper pairs are in a spin-triplet state. Although indirect evidence for such a state has been obtained, the gap structure and pairing symmetry have not so far been determined. Here we report scanning tunnelling spectroscopy of Nb superconducting films proximity coupled to epitaxial Ho. These measurements reveal pronounced changes to the Nb subgap superconducting density of states on driving the Ho through a metamagnetic transition from a helical antiferromagnetic to a homogeneous ferromagnetic state for which a BCS-like gap is recovered. The results prove odd frequency spin-triplet superconductivity at superconductor/inhomogeneous magnet interfaces.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The theory of superconductivity developed by Bardeen, Cooper and Schrieffer (BCS) explains the stabilization of electron pairs into a spin-singlet, even frequency, state by the formation of an energy gap within which the density of states is zero. At a superconductor interface with an inhomogeneous ferromagnet, a gapless odd frequency superconducting state is predicted, in which the Cooper pairs are in a spin-triplet state. Although indirect evidence for such a state has been obtained, the gap structure and pairing symmetry have not so far been determined. Here we report scanning tunnelling spectroscopy of Nb superconducting films proximity coupled to epitaxial Ho. These measurements reveal pronounced changes to the Nb subgap superconducting density of states on driving the Ho through a metamagnetic transition from a helical antiferromagnetic to a homogeneous ferromagnetic state for which a BCS-like gap is recovered. The results prove odd frequency spin-triplet superconductivity at superconductor/inhomogeneous magnet interfaces.
113.
Griffin, John M; Forse, Alexander C; Wang, Hao; Trease, Nicole M; Taberna, Pierre-Louis; Simon, Patrice; Grey, Clare P
Ion counting in supercapacitor electrodes using NMR spectroscopy Journal Article
In: Faraday discussions, vol. 176, pp. 49–68, 2015.
@article{griffin2015ion,
title = {Ion counting in supercapacitor electrodes using NMR spectroscopy},
author = {John M Griffin and Alexander C Forse and Hao Wang and Nicole M Trease and Pierre-Louis Taberna and Patrice Simon and Clare P Grey},
url = {https://pubs.rsc.org/en/content/articlelanding/fd/2014/c4fd00138a#!divAbstract},
year = {2015},
date = {2015-01-01},
journal = {Faraday discussions},
volume = {176},
pages = {49--68},
publisher = {The Royal Society of Chemistry},
abstract = {19F NMR spectroscopy has been used to study the local environments of anions in supercapacitor electrodes and to quantify changes in the populations of adsorbed species during charging. In the absence of an applied potential, anionic species adsorbed within carbon micropores (in-pore) are distinguished from those in large mesopores and spaces between particles (ex-pore) by a characteristic nucleus-independent chemical shift (NICS). Adsorption experiments and two-dimensional exchange experiments confirm that anions are in dynamic equilibrium between the in- and ex-pore environments with an exchange rate in the order of tens of Hz. 19F in situ NMR spectra recorded at different charge states reveal changes in the intensity and NICS of the in-pore resonances, which are interpreted in term of changes in the population and local environments of the adsorbed anions that arise due to the charge-storage process. A comparison of the results obtained for a range of electrolytes reveals that several factors influence the charging mechanism. For a tetraethylammonium tetrafluoroborate electrolyte, positive polarisation of the electrode is found to proceed by anion adsorption at a low concentration, whereas increased ion exchange plays a more important role for a high concentration electrolyte. In contrast, negative polarization of the electrode proceeds by cation adsorption for both concentrations. For a tetrabutylammonium tetrafluoroborate electrolyte, anion expulsion is observed in the negative charging regime; this is attributed to the reduced mobility and/or access of the larger cations inside the pores, which forces the expulsion of anions in order to build up ionic charge. Significant anion expulsion is also observed in the negative charging regime for alkali metal bis(trifluoromethane)sulfonimide electrolytes, suggesting that more subtle factors also affect the charging mechanism.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
19F NMR spectroscopy has been used to study the local environments of anions in supercapacitor electrodes and to quantify changes in the populations of adsorbed species during charging. In the absence of an applied potential, anionic species adsorbed within carbon micropores (in-pore) are distinguished from those in large mesopores and spaces between particles (ex-pore) by a characteristic nucleus-independent chemical shift (NICS). Adsorption experiments and two-dimensional exchange experiments confirm that anions are in dynamic equilibrium between the in- and ex-pore environments with an exchange rate in the order of tens of Hz. 19F in situ NMR spectra recorded at different charge states reveal changes in the intensity and NICS of the in-pore resonances, which are interpreted in term of changes in the population and local environments of the adsorbed anions that arise due to the charge-storage process. A comparison of the results obtained for a range of electrolytes reveals that several factors influence the charging mechanism. For a tetraethylammonium tetrafluoroborate electrolyte, positive polarisation of the electrode is found to proceed by anion adsorption at a low concentration, whereas increased ion exchange plays a more important role for a high concentration electrolyte. In contrast, negative polarization of the electrode proceeds by cation adsorption for both concentrations. For a tetrabutylammonium tetrafluoroborate electrolyte, anion expulsion is observed in the negative charging regime; this is attributed to the reduced mobility and/or access of the larger cations inside the pores, which forces the expulsion of anions in order to build up ionic charge. Significant anion expulsion is also observed in the negative charging regime for alkali metal bis(trifluoromethane)sulfonimide electrolytes, suggesting that more subtle factors also affect the charging mechanism.