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
2017
212.
Vladimir Turek Giuliana Di Martino, Anna Lombardi; Baumberg, Jeremy J
Tracking nanoelectrochemistry using individual plasmonic nanocavities Journal Article
In: Nano letters, vol. 17, no. 8, pp. 4840–4845, 2017.
@article{di2017tracking,
title = {Tracking nanoelectrochemistry using individual plasmonic nanocavities},
author = {Giuliana Di Martino, Vladimir Turek, Anna Lombardi, Ildikó Szabó, Bart De Nijs, Axel Kuhn, E Rosta and Jeremy J Baumberg},
url = {https://pubs.acs.org/doi/abs/10.1021/acs.nanolett.7b01676},
year = {2017},
date = {2017-01-01},
journal = {Nano letters},
volume = {17},
number = {8},
pages = {4840--4845},
publisher = {American Chemical Society},
abstract = {We study in real time the optical response of individual plasmonic nanoparticles on a mirror, utilized as electrodes in an electrochemical cell when a voltage is applied. In this geometry, Au nanoparticles are separated from a bulk Au film by an ultrathin molecular spacer. The nanoscale plasmonic hotspot underneath the nanoparticles locally reveals the modified charge on the Au surface and changes in the polarizability of the molecular spacer. Dark-field and Raman spectroscopy performed on the same nanoparticle show our ability to exploit isolated plasmonic junctions to track the dynamics of nanoelectrochemistry. Enhancements in Raman emission and blue-shifts at a negative potential show the ability to shift electrons within the gap molecules.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
We study in real time the optical response of individual plasmonic nanoparticles on a mirror, utilized as electrodes in an electrochemical cell when a voltage is applied. In this geometry, Au nanoparticles are separated from a bulk Au film by an ultrathin molecular spacer. The nanoscale plasmonic hotspot underneath the nanoparticles locally reveals the modified charge on the Au surface and changes in the polarizability of the molecular spacer. Dark-field and Raman spectroscopy performed on the same nanoparticle show our ability to exploit isolated plasmonic junctions to track the dynamics of nanoelectrochemistry. Enhancements in Raman emission and blue-shifts at a negative potential show the ability to shift electrons within the gap molecules.
211.
Schmidt, Mikołaj K; Esteban, Ruben; Benz, Felix; Baumberg, Jeremy J; Aizpurua, Javier
Linking classical and molecular optomechanics descriptions of SERS Journal Article
In: Faraday discussions, vol. 205, pp. 31–65, 2017.
@article{schmidt2017linking,
title = {Linking classical and molecular optomechanics descriptions of SERS},
author = {Miko{ł}aj K Schmidt and Ruben Esteban and Felix Benz and Jeremy J Baumberg and Javier Aizpurua},
url = {https://pubs.rsc.org/en/content/articlelanding/fd/2017/c7fd00145b#!divAbstract},
year = {2017},
date = {2017-01-01},
journal = {Faraday discussions},
volume = {205},
pages = {31--65},
publisher = {The Royal Society of Chemistry},
abstract = {The surface-enhanced Raman scattering (SERS) of molecular species in plasmonic cavities can be described as an optomechanical process where plasmons constitute an optical cavity of reduced effective mode volume which effectively couples to the vibrations of the molecules. An optomechanical Hamiltonian can address the full quantum dynamics of the system, including the phonon population build-up, the vibrational pumping regime, and the Stokes–anti-Stokes correlations of the photons emitted. Here we describe in detail two different levels of approximation to the methodological solution of the optomechanical Hamiltonian of a generic SERS configuration, and compare the results of each model in light of recent experiments. Furthermore, a phenomenological semi-classical approach based on a rate equation of the phonon population is demonstrated to be formally equivalent to that obtained from the full quantum optomechanical approach. The evolution of the Raman signal with laser intensity (thermal, vibrational pumping and instability regimes) is accurately addressed when this phenomenological semi-classical approach is properly extended to account for the anti-Stokes process. The formal equivalence between semi-classical and molecular optomechanics descriptions allows us to describe the vibrational pumping regime of SERS through the classical cross sections which characterize a nanosystem, thus setting a roadmap to describing molecular optomechanical effects in a variety of experimental situations.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The surface-enhanced Raman scattering (SERS) of molecular species in plasmonic cavities can be described as an optomechanical process where plasmons constitute an optical cavity of reduced effective mode volume which effectively couples to the vibrations of the molecules. An optomechanical Hamiltonian can address the full quantum dynamics of the system, including the phonon population build-up, the vibrational pumping regime, and the Stokes–anti-Stokes correlations of the photons emitted. Here we describe in detail two different levels of approximation to the methodological solution of the optomechanical Hamiltonian of a generic SERS configuration, and compare the results of each model in light of recent experiments. Furthermore, a phenomenological semi-classical approach based on a rate equation of the phonon population is demonstrated to be formally equivalent to that obtained from the full quantum optomechanical approach. The evolution of the Raman signal with laser intensity (thermal, vibrational pumping and instability regimes) is accurately addressed when this phenomenological semi-classical approach is properly extended to account for the anti-Stokes process. The formal equivalence between semi-classical and molecular optomechanics descriptions allows us to describe the vibrational pumping regime of SERS through the classical cross sections which characterize a nanosystem, thus setting a roadmap to describing molecular optomechanical effects in a variety of experimental situations.
210.
Hu, Guohua; Albrow-Owen, Tom; Jin, Xinxin; Ali, Ayaz; Hu, Yuwei; Howe, Richard CT; Shehzad, Khurram; Yang, Zongyin; Zhu, Xuekun; Woodward, Robert I; others,
Black phosphorus ink formulation for inkjet printing of optoelectronics and photonics Journal Article
In: Nature communications, vol. 8, no. 1, pp. 1–10, 2017.
@article{hu2017black,
title = {Black phosphorus ink formulation for inkjet printing of optoelectronics and photonics},
author = {Guohua Hu and Tom Albrow-Owen and Xinxin Jin and Ayaz Ali and Yuwei Hu and Richard CT Howe and Khurram Shehzad and Zongyin Yang and Xuekun Zhu and Robert I Woodward and others},
url = {https://www.nature.com/articles/s41467-017-00358-1},
year = {2017},
date = {2017-01-01},
journal = {Nature communications},
volume = {8},
number = {1},
pages = {1--10},
publisher = {Nature Publishing Group},
abstract = {Black phosphorus is a two-dimensional material of great interest, in part because of its high carrier mobility and thickness dependent direct bandgap. However, its instability under ambient conditions limits material deposition options for device fabrication. Here we show a black phosphorus ink that can be reliably inkjet printed, enabling scalable development of optoelectronic and photonic devices. Our binder-free ink suppresses coffee ring formation through induced recirculating Marangoni flow, and supports excellent consistency (< 2% variation) and spatial uniformity (< 3.4% variation), without substrate pre-treatment. Due to rapid ink drying (< 10 s at < 60 °C), printing causes minimal oxidation. Following encapsulation, the printed black phosphorus is stable against long-term (> 30 days) oxidation. We demonstrate printed black phosphorus as a passive switch for ultrafast lasers, stable against intense irradiation, and as a visible to near-infrared photodetector with high responsivities. Our work highlights the promise of this material as a functional ink platform for printed devices.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Black phosphorus is a two-dimensional material of great interest, in part because of its high carrier mobility and thickness dependent direct bandgap. However, its instability under ambient conditions limits material deposition options for device fabrication. Here we show a black phosphorus ink that can be reliably inkjet printed, enabling scalable development of optoelectronic and photonic devices. Our binder-free ink suppresses coffee ring formation through induced recirculating Marangoni flow, and supports excellent consistency (< 2% variation) and spatial uniformity (< 3.4% variation), without substrate pre-treatment. Due to rapid ink drying (< 10 s at < 60 °C), printing causes minimal oxidation. Following encapsulation, the printed black phosphorus is stable against long-term (> 30 days) oxidation. We demonstrate printed black phosphorus as a passive switch for ultrafast lasers, stable against intense irradiation, and as a visible to near-infrared photodetector with high responsivities. Our work highlights the promise of this material as a functional ink platform for printed devices.
209.
![Smart supramolecular sensing with cucurbit [n] urils: probing hydrogen bonding with SERS](https://pubs.rsc.org/image/article/2017/fd/c7fd00147a/c7fd00147a-f1.gif)
de Nijs, Bart; Kamp, Marlous; Szabó, Istvan; Barrow, Steven J; Benz, Felix; Wu, Guanglu; Carnegie, Cloudy; Chikkaraddy, Rohit; Wang, Wenting; Deacon, William M; others,
Smart supramolecular sensing with cucurbit [n] urils: probing hydrogen bonding with SERS Journal Article
In: Faraday discussions, vol. 205, pp. 505–515, 2017.
@article{de2017smart,
title = {Smart supramolecular sensing with cucurbit [n] urils: probing hydrogen bonding with SERS},
author = {Bart de Nijs and Marlous Kamp and Istvan Szabó and Steven J Barrow and Felix Benz and Guanglu Wu and Cloudy Carnegie and Rohit Chikkaraddy and Wenting Wang and William M Deacon and others},
url = {https://pubs.rsc.org/en/content/articlelanding/fd/2017/c7fd00147a#!divAbstract},
year = {2017},
date = {2017-01-01},
journal = {Faraday discussions},
volume = {205},
pages = {505--515},
publisher = {The Royal Society of Chemistry},
abstract = {Rigid gap nano-aggregates of Au nanoparticles formed using cucurbit[n]uril (CB[n]) molecules are used to investigate the competitive binding of ethanol and methanol in an aqueous environment. We show it is possible to detect as little as 0.1% methanol in water and a ten times higher affinity to methanol over ethanol, making this a useful technology for quality control in alcohol production. We demonstrate strong interaction effects in the SERS peaks, which we demonstrate are likely from the hydrogen bonding of water complexes in the vicinity of the CB[n]s.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Rigid gap nano-aggregates of Au nanoparticles formed using cucurbit[n]uril (CB[n]) molecules are used to investigate the competitive binding of ethanol and methanol in an aqueous environment. We show it is possible to detect as little as 0.1% methanol in water and a ten times higher affinity to methanol over ethanol, making this a useful technology for quality control in alcohol production. We demonstrate strong interaction effects in the SERS peaks, which we demonstrate are likely from the hydrogen bonding of water complexes in the vicinity of the CB[n]s.
208.
Guohua Hu Xinxin Jin, Meng Zhang; Hasan, Tawfique
Long term stable black phosphorus saturable absorber for mode-locked fiber laser Proceedings Article
In: CLEO: Science and Innovations, pp. SW4K–1, Optical Society of America 2017.
@inproceedings{jin2017long,
title = {Long term stable black phosphorus saturable absorber for mode-locked fiber laser},
author = {Xinxin Jin, Guohua Hu, Meng Zhang, Yanguang Hu, Tom Albrow-Owen, Richard C. T. Howe, Tien-Chun Wu, X Zhu, Zheng Zheng and Tawfique Hasan},
url = {https://www.osapublishing.org/abstract.cfm?uri=CLEO_SI-2017-SW4K.1},
year = {2017},
date = {2017-01-01},
booktitle = {CLEO: Science and Innovations},
pages = {SW4K--1},
organization = {Optical Society of America},
abstract = {We demonstrate a long-term stable fiber laser mode-locked by a solution deposited and encapsulated black phosphorus (BP) saturable absorber. Our work highlights the potential of BP-based devices for photonic applications when operating under ambient conditions.},
keywords = {},
pubstate = {published},
tppubtype = {inproceedings}
}
We demonstrate a long-term stable fiber laser mode-locked by a solution deposited and encapsulated black phosphorus (BP) saturable absorber. Our work highlights the potential of BP-based devices for photonic applications when operating under ambient conditions.
207.
Mansell, Rhodri; Vemulkar, Tarun; Petit, Dorothée CMC; Cheng, Yu; Murphy, Jason; Lesniak, Maciej S; Cowburn, Russell P
Magnetic particles with perpendicular anisotropy for mechanical cancer cell destruction Journal Article
In: Scientific reports, vol. 7, no. 1, pp. 1–7, 2017.
@article{mansell2017magnetic,
title = {Magnetic particles with perpendicular anisotropy for mechanical cancer cell destruction},
author = {Rhodri Mansell and Tarun Vemulkar and Dorothée CMC Petit and Yu Cheng and Jason Murphy and Maciej S Lesniak and Russell P Cowburn},
url = {https://www.nature.com/articles/s41598-017-04154-1},
year = {2017},
date = {2017-01-01},
journal = {Scientific reports},
volume = {7},
number = {1},
pages = {1--7},
publisher = {Nature Publishing Group},
abstract = {We demonstrate the effectiveness of out-of-plane magnetized magnetic microdiscs for cancer treatment through mechanical cell disruption under an applied rotating magnetic field. The magnetic particles are synthetic antiferromagnets formed from a repeated motif of ultrathin CoFeB/Pt layers. In-vitro studies on glioma cells are used to compare the efficiency of the CoFeB/Pt microdiscs with Py vortex microdiscs. It is found that the CoFeB/Pt microdiscs are able to damage 62 ± 3% of cancer cells compared with 12 ± 2% after applying a 10 kOe rotating field for one minute. The torques applied by each type of particle are measured and are shown to match values predicted by a simple Stoner-Wohlfarth anisotropy model, giving maximum values of 20 fNm for the CoFeB/Pt and 75 fNm for the Py vortex particles. The symmetry of the anisotropy is argued to be more important than the magnitude of the torque in causing effective cell destruction in these experiments. This work shows how future magnetic particles can be successfully designed for applications requiring control of applied torques.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
We demonstrate the effectiveness of out-of-plane magnetized magnetic microdiscs for cancer treatment through mechanical cell disruption under an applied rotating magnetic field. The magnetic particles are synthetic antiferromagnets formed from a repeated motif of ultrathin CoFeB/Pt layers. In-vitro studies on glioma cells are used to compare the efficiency of the CoFeB/Pt microdiscs with Py vortex microdiscs. It is found that the CoFeB/Pt microdiscs are able to damage 62 ± 3% of cancer cells compared with 12 ± 2% after applying a 10 kOe rotating field for one minute. The torques applied by each type of particle are measured and are shown to match values predicted by a simple Stoner-Wohlfarth anisotropy model, giving maximum values of 20 fNm for the CoFeB/Pt and 75 fNm for the Py vortex particles. The symmetry of the anisotropy is argued to be more important than the magnitude of the torque in causing effective cell destruction in these experiments. This work shows how future magnetic particles can be successfully designed for applications requiring control of applied torques.
206.
Srivastava, Anand; Robinson, Jason; Blamire, Mark; Komori, S; Bernardo, Angelo Di; Montero, Mario Amado; Garcia, Carla Palomares
Research data: Magnetization-control and transfer of spin-polarized Cooper pairs into a half-metal manganite Journal Article
In: 2017.
@article{srivastava2017research,
title = {Research data: Magnetization-control and transfer of spin-polarized Cooper pairs into a half-metal manganite},
author = {Anand Srivastava and Jason Robinson and Mark Blamire and S Komori and Angelo Di Bernardo and Mario Amado Montero and Carla Palomares Garcia},
url = {https://www.repository.cam.ac.uk/handle/1810/267803},
year = {2017},
date = {2017-01-01},
abstract = {Origin windows of all figures in the article},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Origin windows of all figures in the article
205.
Bulmer, John S; Gspann, Thurid S; Orozco, Francisco; Sparkes, Martin; Koerner, Hilmar; Bernardo, Angelo Di; Niemiec, Arkadiusz; Robinson, Jason WA; Koziol, Krzysztof K; Elliott, James A; others,
Photonic sorting of aligned, crystalline carbon nanotube textiles Journal Article
In: Scientific reports, vol. 7, no. 1, pp. 1–11, 2017.
@article{bulmer2017photonic,
title = {Photonic sorting of aligned, crystalline carbon nanotube textiles},
author = {John S Bulmer and Thurid S Gspann and Francisco Orozco and Martin Sparkes and Hilmar Koerner and Angelo Di Bernardo and Arkadiusz Niemiec and Jason WA Robinson and Krzysztof K Koziol and James A Elliott and others},
url = {https://www.nature.com/articles/s41598-017-12605-y},
year = {2017},
date = {2017-01-01},
journal = {Scientific reports},
volume = {7},
number = {1},
pages = {1--11},
publisher = {Nature Publishing Group},
abstract = {Floating catalyst chemical vapor deposition uniquely generates aligned carbon nanotube (CNT) textiles with individual CNT lengths magnitudes longer than competing processes, though hindered by impurities and intrinsic/extrinsic defects. We present a photonic-based post-process, particularly suited for these textiles, that selectively removes defective CNTs and other carbons not forming a threshold thermal pathway. In this method, a large diameter laser beam rasters across the surface of a partly aligned CNT textile in air, suspended from its ends. This results in brilliant, localized oxidation, where remaining material is an optically transparent film comprised of few-walled CNTs with profound and unique improvement in microstructure alignment and crystallinity. Raman spectroscopy shows substantial D peak suppression while preserving radial breathing modes. This increases the undoped, specific electrical conductivity at least an order of magnitude to beyond that of single-crystal graphite. Cryogenic conductivity measurements indicate intrinsic transport enhancement, opposed to simply removing nonconductive carbons/residual catalyst.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Floating catalyst chemical vapor deposition uniquely generates aligned carbon nanotube (CNT) textiles with individual CNT lengths magnitudes longer than competing processes, though hindered by impurities and intrinsic/extrinsic defects. We present a photonic-based post-process, particularly suited for these textiles, that selectively removes defective CNTs and other carbons not forming a threshold thermal pathway. In this method, a large diameter laser beam rasters across the surface of a partly aligned CNT textile in air, suspended from its ends. This results in brilliant, localized oxidation, where remaining material is an optically transparent film comprised of few-walled CNTs with profound and unique improvement in microstructure alignment and crystallinity. Raman spectroscopy shows substantial D peak suppression while preserving radial breathing modes. This increases the undoped, specific electrical conductivity at least an order of magnitude to beyond that of single-crystal graphite. Cryogenic conductivity measurements indicate intrinsic transport enhancement, opposed to simply removing nonconductive carbons/residual catalyst.
204.
Guttenplan, Alexander PM; Young, Laurence J; Matak-Vinkovic, Dijana; Kaminski, Clemens F; Knowles, Tuomas PJ; Itzhaki, Laura S
Nanoscale click-reactive scaffolds from peptide self-assembly Journal Article
In: Journal of nanobiotechnology, vol. 15, no. 1, pp. 1–8, 2017.
@article{guttenplan2017nanoscale,
title = {Nanoscale click-reactive scaffolds from peptide self-assembly},
author = {Alexander PM Guttenplan and Laurence J Young and Dijana Matak-Vinkovic and Clemens F Kaminski and Tuomas PJ Knowles and Laura S Itzhaki},
url = {https://jnanobiotechnology.biomedcentral.com/articles/10.1186/s12951-017-0300-7},
year = {2017},
date = {2017-01-01},
journal = {Journal of nanobiotechnology},
volume = {15},
number = {1},
pages = {1--8},
publisher = {BioMed Central},
abstract = {Due to their natural tendency to self-assemble, proteins and peptides are important components for organic nanotechnology. One particular class of peptides of recent interest is those that form amyloid fibrils, as this self-assembly results in extremely strong, stable quasi-one-dimensional structures which can be used to organise a wide range of cargo species including proteins and oligonucleotides. However, assembly of peptides already conjugated to proteins is limited to cargo species that do not interfere sterically with the assembly process or misfold under the harsh conditions often used for assembly. Therefore, a general method is needed to conjugate proteins and other molecules to amyloid fibrils after the fibrils have self-assembled.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Due to their natural tendency to self-assemble, proteins and peptides are important components for organic nanotechnology. One particular class of peptides of recent interest is those that form amyloid fibrils, as this self-assembly results in extremely strong, stable quasi-one-dimensional structures which can be used to organise a wide range of cargo species including proteins and oligonucleotides. However, assembly of peptides already conjugated to proteins is limited to cargo species that do not interfere sterically with the assembly process or misfold under the harsh conditions often used for assembly. Therefore, a general method is needed to conjugate proteins and other molecules to amyloid fibrils after the fibrils have self-assembled.
203.
Challa, Pavan K; Kartanas, Tadas; Charmet, Jér^ome; Knowles, Tuomas PJ
Microfluidic devices fabricated using fast wafer-scale LED-lithography patterning Journal Article
In: Biomicrofluidics, vol. 11, no. 1, pp. 014113, 2017.
@article{challa2017microfluidic,
title = {Microfluidic devices fabricated using fast wafer-scale LED-lithography patterning},
author = {Pavan K Challa and Tadas Kartanas and Jér{^o}me Charmet and Tuomas PJ Knowles},
url = {https://aip.scitation.org/doi/abs/10.1063/1.4976690},
year = {2017},
date = {2017-01-01},
journal = {Biomicrofluidics},
volume = {11},
number = {1},
pages = {014113},
publisher = {AIP Publishing LLC},
abstract = {Current lithography approaches underpinning the fabrication of microfluidic devices rely on UV exposure of photoresists to define microstructures in these materials. Conventionally, this objective is achieved with gas discharge mercury lamps, which are capable of producing high intensity UV radiation. However, these sources are costly, have a comparatively short lifetime, necessitate regular calibration, and require significant time to warm up prior to exposure taking place. To address these limitations we exploit advances in solid state sources in the UV range and describe a fast and robust wafer-scale laboratory exposure system relying entirely on UV-Light emitting diode (UV-LED) illumination. As an illustration of the potential of this system for fast and low-cost microfluidic device production, we demonstrate the microfabrication of a 3D spray-drying microfluidic device and a 3D double junction microdroplet maker device.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Current lithography approaches underpinning the fabrication of microfluidic devices rely on UV exposure of photoresists to define microstructures in these materials. Conventionally, this objective is achieved with gas discharge mercury lamps, which are capable of producing high intensity UV radiation. However, these sources are costly, have a comparatively short lifetime, necessitate regular calibration, and require significant time to warm up prior to exposure taking place. To address these limitations we exploit advances in solid state sources in the UV range and describe a fast and robust wafer-scale laboratory exposure system relying entirely on UV-Light emitting diode (UV-LED) illumination. As an illustration of the potential of this system for fast and low-cost microfluidic device production, we demonstrate the microfabrication of a 3D spray-drying microfluidic device and a 3D double junction microdroplet maker device.
202.
Kartanas, Tadas; Ostanin, Victor; Challa, Pavan Kumar; Daly, Ronan; Charmet, Jerome; Knowles, Tuomas PJ
Enhanced quality factor label-free biosensing with micro-cantilevers integrated into microfluidic systems Journal Article
In: Analytical chemistry, vol. 89, no. 22, pp. 11929–11936, 2017.
@article{kartanas2017enhanced,
title = {Enhanced quality factor label-free biosensing with micro-cantilevers integrated into microfluidic systems},
author = {Tadas Kartanas and Victor Ostanin and Pavan Kumar Challa and Ronan Daly and Jerome Charmet and Tuomas PJ Knowles},
url = {https://pubs.acs.org/doi/abs/10.1021/acs.analchem.7b01174},
year = {2017},
date = {2017-01-01},
journal = {Analytical chemistry},
volume = {89},
number = {22},
pages = {11929--11936},
publisher = {American Chemical Society},
abstract = {Microelectromechanical systems (MEMS) have enabled the development of a new generation of sensor platforms. Acoustic sensor operation in liquid, the native environment of biomolecules, causes, however, significant degradation of sensing performance due to viscous drag and relies on the availability of capture molecules to bind analytes of interest to the sensor surface. Here, we describe a strategy to interface MEMS sensors with microfluidic platforms through an aerosol spray. Our sensing platform comprises a microfluidic spray nozzle and a microcantilever array operated in dynamic mode within a closed loop oscillator. A solution containing the analyte is sprayed uniformly through picoliter droplets onto the microcantilever surface; the micrometer-scale drops evaporate rapidly and leave the solutes behind, adding to the mass of the cantilever. This sensing scheme results in a 50-fold increase in the quality factor compared to operation in liquid, yet allows the analytes to be introduced into the sensing system from a solution phase. It achieves a 370 femtogram limit of detection, and we demonstrate quantitative label-free analysis of inorganic salts and model proteins. These results demonstrate that the standard resolution limits of cantilever sensing in dynamic mode can be overcome with the integration of spray microfluidics with MEMS.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Microelectromechanical systems (MEMS) have enabled the development of a new generation of sensor platforms. Acoustic sensor operation in liquid, the native environment of biomolecules, causes, however, significant degradation of sensing performance due to viscous drag and relies on the availability of capture molecules to bind analytes of interest to the sensor surface. Here, we describe a strategy to interface MEMS sensors with microfluidic platforms through an aerosol spray. Our sensing platform comprises a microfluidic spray nozzle and a microcantilever array operated in dynamic mode within a closed loop oscillator. A solution containing the analyte is sprayed uniformly through picoliter droplets onto the microcantilever surface; the micrometer-scale drops evaporate rapidly and leave the solutes behind, adding to the mass of the cantilever. This sensing scheme results in a 50-fold increase in the quality factor compared to operation in liquid, yet allows the analytes to be introduced into the sensing system from a solution phase. It achieves a 370 femtogram limit of detection, and we demonstrate quantitative label-free analysis of inorganic salts and model proteins. These results demonstrate that the standard resolution limits of cantilever sensing in dynamic mode can be overcome with the integration of spray microfluidics with MEMS.
201.
Tait, Edward; Ducati, Caterina; Payne, Mike; Hine, Nicholas
Oxygen Vacancies in the Anatase (101) Surface: Formation Energies and Finite Size Effects Proceedings Article
In: APS March Meeting Abstracts, pp. C28–009, 2017.
@inproceedings{tait2017oxygen,
title = {Oxygen Vacancies in the Anatase (101) Surface: Formation Energies and Finite Size Effects},
author = {Edward Tait and Caterina Ducati and Mike Payne and Nicholas Hine},
url = {https://ui.adsabs.harvard.edu/abs/2017APS..MARC28009T/abstract},
year = {2017},
date = {2017-01-01},
booktitle = {APS March Meeting Abstracts},
volume = {2017},
pages = {C28--009},
abstract = {We present a study of oxygen vacancies in the anatase TiO2 (101) surface. We take great care to minimise the impact of periodic boundary conditions on our results. We make use of the ONETEP linear scaling DFT code to study defects in large (order 800 atom) simulation cells, to reduce long range strain interactions. We also make use of a scheme to correct for spurious periodic electrostatic interactions in the case of charged defects. Finally we study the behaviour of defect formation energies as a function of distance from the surface, and demonstrate convergence to bulk formation energies with depth. We also present novel functionality for EELS calculations within LS-DFT, suitable for large nanomaterials systems.},
keywords = {},
pubstate = {published},
tppubtype = {inproceedings}
}
We present a study of oxygen vacancies in the anatase TiO2 (101) surface. We take great care to minimise the impact of periodic boundary conditions on our results. We make use of the ONETEP linear scaling DFT code to study defects in large (order 800 atom) simulation cells, to reduce long range strain interactions. We also make use of a scheme to correct for spurious periodic electrostatic interactions in the case of charged defects. Finally we study the behaviour of defect formation energies as a function of distance from the surface, and demonstrate convergence to bulk formation energies with depth. We also present novel functionality for EELS calculations within LS-DFT, suitable for large nanomaterials systems.
200.
Booker, Edward P; Thomas, Tudor H; Quarti, Claudio; Stanton, Michael R; Dashwood, Cameron D; Gillett, Alexander J; Richter, Johannes M; Pearson, Andrew J; Davis, Nathaniel JLK; Sirringhaus, Henning; others,
Formation of long-lived color centers for broadband visible light emission in low-dimensional layered perovskites Journal Article
In: Journal of the American Chemical Society, vol. 139, no. 51, pp. 18632–18639, 2017.
@article{booker2017formation,
title = {Formation of long-lived color centers for broadband visible light emission in low-dimensional layered perovskites},
author = {Edward P Booker and Tudor H Thomas and Claudio Quarti and Michael R Stanton and Cameron D Dashwood and Alexander J Gillett and Johannes M Richter and Andrew J Pearson and Nathaniel JLK Davis and Henning Sirringhaus and others},
url = {https://pubs.acs.org/doi/abs/10.1021/jacs.7b10223},
year = {2017},
date = {2017-01-01},
journal = {Journal of the American Chemical Society},
volume = {139},
number = {51},
pages = {18632--18639},
publisher = {American Chemical Society},
abstract = {We investigate the origin of the broadband visible emission in layered hybrid lead-halide perovskites and its connection with structural and photophysical properties. We study ⟨001⟩ oriented thin films of hexylammonium (HA) lead iodide, (C6H16N)2PbI4, and dodecylammonium (DA) lead iodide, (C12H28N)2PbI4, by combining first-principles simulations with time-resolved photoluminescence, steady-state absorption and X-ray diffraction measurements on cooling from 300 to 4 K. Ultrafast transient absorption and photoluminescence measurements are used to track the formation and recombination of emissive states. In addition to the excitonic photoluminescence near the absorption edge, we find a red-shifted, broadband (full-width at half-maximum of about 0.4 eV), emission band below 200 K, similar to emission from ⟨110⟩ oriented bromide 2D perovskites at room temperature. The lifetime of this sub-band-gap emission exceeds that of the excitonic transition by orders of magnitude. We use X-ray diffraction measurements to study the changes in crystal lattice with temperature. We report changes in the octahedral tilt and lattice spacing in both materials, together with a phase change around 200 K in DA2PbI4. DFT simulations of the HA2PbI4 crystal structure indicate that the low-energy emission is due to interstitial iodide and related Frenkel defects. Our results demonstrate that white-light emission is not limited to ⟨110⟩ oriented bromide 2D perovskites but a general property of this class of system, and highlight the importance of defect control for the formation of low-energy emissive sites, which can provide a pathway to design tailored white-light emitters.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
We investigate the origin of the broadband visible emission in layered hybrid lead-halide perovskites and its connection with structural and photophysical properties. We study ⟨001⟩ oriented thin films of hexylammonium (HA) lead iodide, (C6H16N)2PbI4, and dodecylammonium (DA) lead iodide, (C12H28N)2PbI4, by combining first-principles simulations with time-resolved photoluminescence, steady-state absorption and X-ray diffraction measurements on cooling from 300 to 4 K. Ultrafast transient absorption and photoluminescence measurements are used to track the formation and recombination of emissive states. In addition to the excitonic photoluminescence near the absorption edge, we find a red-shifted, broadband (full-width at half-maximum of about 0.4 eV), emission band below 200 K, similar to emission from ⟨110⟩ oriented bromide 2D perovskites at room temperature. The lifetime of this sub-band-gap emission exceeds that of the excitonic transition by orders of magnitude. We use X-ray diffraction measurements to study the changes in crystal lattice with temperature. We report changes in the octahedral tilt and lattice spacing in both materials, together with a phase change around 200 K in DA2PbI4. DFT simulations of the HA2PbI4 crystal structure indicate that the low-energy emission is due to interstitial iodide and related Frenkel defects. Our results demonstrate that white-light emission is not limited to ⟨110⟩ oriented bromide 2D perovskites but a general property of this class of system, and highlight the importance of defect control for the formation of low-energy emissive sites, which can provide a pathway to design tailored white-light emitters.
199.
H Fleming Giuliana Di Martino, Marlous Kamp; Lussier, Felix
Highlights from Faraday Discussion FDSERS17: Surface Enhanced Raman Scattering--SERS, Glasgow, UK, 30th August--1st September 2017 Journal Article
In: Chemical Communications, vol. 53, no. 95, pp. 12726–12733, 2017.
@article{di2017highlights,
title = {Highlights from Faraday Discussion FDSERS17: Surface Enhanced Raman Scattering--SERS, Glasgow, UK, 30th August--1st September 2017},
author = {Giuliana Di Martino, H Fleming, Marlous Kamp and Felix Lussier},
url = {https://pubs.rsc.org/lv/content/articlehtml/2017/cc/c7cc90411h},
year = {2017},
date = {2017-01-01},
journal = {Chemical Communications},
volume = {53},
number = {95},
pages = {12726--12733},
publisher = {Royal Society of Chemistry},
abstract = {The 2017 Faraday Discussion on Surface Enhanced Raman Scattering (SERS) attracted more than a hundred delegates from a broad spectrum of backgrounds and experience levels, bringing together leading scientists involved in the long living field of SERS. The meeting gave an overview of the liveliness of the topic, characterised by open questions and fascinating science still to discover. In the following, we discuss the topics covered during this meeting and briefly highlight the content of each presentation.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The 2017 Faraday Discussion on Surface Enhanced Raman Scattering (SERS) attracted more than a hundred delegates from a broad spectrum of backgrounds and experience levels, bringing together leading scientists involved in the long living field of SERS. The meeting gave an overview of the liveliness of the topic, characterised by open questions and fascinating science still to discover. In the following, we discuss the topics covered during this meeting and briefly highlight the content of each presentation.
198.
Joseph, James; Baumann, Kevin N; Koehler, Philipp; Zuehlsdorff, Tim J; Cole, Daniel J; Weber, Judith; Bohndiek, Sarah E; Hernández-Ainsa, Silvia
Distance dependent photoacoustics revealed through DNA nanostructures Journal Article
In: Nanoscale, vol. 9, no. 42, pp. 16193–16199, 2017.
@article{joseph2017distance,
title = {Distance dependent photoacoustics revealed through DNA nanostructures},
author = {James Joseph and Kevin N Baumann and Philipp Koehler and Tim J Zuehlsdorff and Daniel J Cole and Judith Weber and Sarah E Bohndiek and Silvia Hernández-Ainsa},
url = {https://pubs.rsc.org/en/content/articlelanding/2017/nr/c7nr05353c/unauth#!divAbstract},
year = {2017},
date = {2017-01-01},
journal = {Nanoscale},
volume = {9},
number = {42},
pages = {16193--16199},
publisher = {Royal Society of Chemistry},
abstract = {Molecular rulers that rely on the Förster resonance energy transfer (FRET) mechanism are widely used to investigate dynamic molecular processes that occur on the nanometer scale. However, the capabilities of these fluorescence molecular rulers are fundamentally limited to shallow imaging depths by light scattering in biological samples. Photoacoustic tomography (PAT) has recently emerged as a high resolution modality for in vivo imaging, coupling optical excitation with ultrasound detection. In this paper, we report the capability of PAT to probe distance-dependent FRET at centimeter depths. Using DNA nanotechnology we created several nanostructures with precisely positioned fluorophore–quencher pairs over a range of nanoscale separation distances. PAT of the DNA nanostructures showed distance-dependent photoacoustic signal enhancement and demonstrated the ability of PAT to reveal the FRET process deep within tissue mimicking phantoms. Further, we experimentally validated these DNA nanostructures as a novel and biocompatible strategy to augment the intrinsic photoacoustic signal generation capabilities of small molecule fluorescent dyes.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Molecular rulers that rely on the Förster resonance energy transfer (FRET) mechanism are widely used to investigate dynamic molecular processes that occur on the nanometer scale. However, the capabilities of these fluorescence molecular rulers are fundamentally limited to shallow imaging depths by light scattering in biological samples. Photoacoustic tomography (PAT) has recently emerged as a high resolution modality for in vivo imaging, coupling optical excitation with ultrasound detection. In this paper, we report the capability of PAT to probe distance-dependent FRET at centimeter depths. Using DNA nanotechnology we created several nanostructures with precisely positioned fluorophore–quencher pairs over a range of nanoscale separation distances. PAT of the DNA nanostructures showed distance-dependent photoacoustic signal enhancement and demonstrated the ability of PAT to reveal the FRET process deep within tissue mimicking phantoms. Further, we experimentally validated these DNA nanostructures as a novel and biocompatible strategy to augment the intrinsic photoacoustic signal generation capabilities of small molecule fluorescent dyes.
197.
Lin, Chun-Yu; Liu, Wei-Lun; Chang, Che-Chia; Chang, Hou-Tai; Hu, Han-Chung; Kao, Kuo-chin; Chen, Ning-Hung; Chen, Ying-Jen; Yang, Cheng-Ta; Huang, Chung-Chi; others,
Invasive fungal tracheobronchitis in mechanically ventilated critically ill patients: underlying conditions, diagnosis, and outcomes Journal Article
In: Annals of intensive care, vol. 7, no. 1, pp. 1–7, 2017.
@article{lin2017invasiveb,
title = {Invasive fungal tracheobronchitis in mechanically ventilated critically ill patients: underlying conditions, diagnosis, and outcomes},
author = {Chun-Yu Lin and Wei-Lun Liu and Che-Chia Chang and Hou-Tai Chang and Han-Chung Hu and Kuo-chin Kao and Ning-Hung Chen and Ying-Jen Chen and Cheng-Ta Yang and Chung-Chi Huang and others},
url = {https://link.springer.com/article/10.1186/s13613-016-0230-9},
year = {2017},
date = {2017-01-01},
journal = {Annals of intensive care},
volume = {7},
number = {1},
pages = {1--7},
publisher = {SpringerOpen},
abstract = {This study included 31 patients who had been diagnosed as having IFT, comprising 24 men and 7 women with a mean age of 64.7 ± 13.7 years. All patients developed respiratory failure and received mechanical ventilation before diagnosis. Eighteen (58.1%) patients had diabetes mellitus, and 12 (38.7%) had chronic lung disease. Four (12.9%) patients had hematologic disease, and none of the patients had neutropenia. Twenty-five (80.6%) patients were diagnosed as having proven IFT, and the remaining patients had probable IFT. Aspergillus spp. (61.3%) were the most common pathogenic species, followed by Mucorales (25.8%) and Candida spp. (6.5%). The diagnoses in six (19.4%) patients were confirmed only through bronchial biopsy and histopathological examination, whereas their cultures of bronchoalveolar lavage fluid were negative for fungi. The overall in-hospital mortality rate was 93.5%.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
This study included 31 patients who had been diagnosed as having IFT, comprising 24 men and 7 women with a mean age of 64.7 ± 13.7 years. All patients developed respiratory failure and received mechanical ventilation before diagnosis. Eighteen (58.1%) patients had diabetes mellitus, and 12 (38.7%) had chronic lung disease. Four (12.9%) patients had hematologic disease, and none of the patients had neutropenia. Twenty-five (80.6%) patients were diagnosed as having proven IFT, and the remaining patients had probable IFT. Aspergillus spp. (61.3%) were the most common pathogenic species, followed by Mucorales (25.8%) and Candida spp. (6.5%). The diagnoses in six (19.4%) patients were confirmed only through bronchial biopsy and histopathological examination, whereas their cultures of bronchoalveolar lavage fluid were negative for fungi. The overall in-hospital mortality rate was 93.5%.
196.
Moyroud, Edwige; Wenzel, Tobias; Middleton, Rox; Rudall, Paula J; Banks, Hannah; Reed, Alison; Mellers, Greg; Killoran, Patrick; Westwood, Murphy M; Steiner, Ullrich; others,
Disorder in convergent floral nanostructures enhances signalling to bees Journal Article
In: Nature, vol. 550, no. 7677, pp. 469–474, 2017.
@article{moyroud2017disorder,
title = {Disorder in convergent floral nanostructures enhances signalling to bees},
author = {Edwige Moyroud and Tobias Wenzel and Rox Middleton and Paula J Rudall and Hannah Banks and Alison Reed and Greg Mellers and Patrick Killoran and Murphy M Westwood and Ullrich Steiner and others},
url = {https://www.nature.com/articles/nature24285},
year = {2017},
date = {2017-01-01},
journal = {Nature},
volume = {550},
number = {7677},
pages = {469--474},
publisher = {Nature Publishing Group},
abstract = {Diverse forms of nanoscale architecture generate structural colour and perform signalling functions within and between species. Structural colour is the result of the interference of light from approximately regular periodic structures; some structural disorder is, however, inevitable in biological organisms. Is this disorder functional and subject to evolutionary selection, or is it simply an unavoidable outcome of biological developmental processes? Here we show that disordered nanostructures enable flowers to produce visual signals that are salient to bees. These disordered nanostructures (identified in most major lineages of angiosperms) have distinct anatomies but convergent optical properties; they all produce angle-dependent scattered light, predominantly at short wavelengths (ultraviolet and blue). We manufactured artificial flowers with nanoscale structures that possessed tailored levels of disorder in order to investigate how foraging bumblebees respond to this optical effect. We conclude that floral nanostructures have evolved, on multiple independent occasions, an effective degree of relative spatial disorder that generates a photonic signature that is highly salient to insect pollinators.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Diverse forms of nanoscale architecture generate structural colour and perform signalling functions within and between species. Structural colour is the result of the interference of light from approximately regular periodic structures; some structural disorder is, however, inevitable in biological organisms. Is this disorder functional and subject to evolutionary selection, or is it simply an unavoidable outcome of biological developmental processes? Here we show that disordered nanostructures enable flowers to produce visual signals that are salient to bees. These disordered nanostructures (identified in most major lineages of angiosperms) have distinct anatomies but convergent optical properties; they all produce angle-dependent scattered light, predominantly at short wavelengths (ultraviolet and blue). We manufactured artificial flowers with nanoscale structures that possessed tailored levels of disorder in order to investigate how foraging bumblebees respond to this optical effect. We conclude that floral nanostructures have evolved, on multiple independent occasions, an effective degree of relative spatial disorder that generates a photonic signature that is highly salient to insect pollinators.
195.
Jin, Xinxin; Hu, Guohua; Zhang, Meng; Hu, Yuwei; Albrow-Owen, Tom; Howe, Richard CT; Wu, Tien-Chun; Zhu, Xuekun; Zheng, Zheng; Hasan, Tawfique
Wideband tunable ultrafast fiber laser using blackphosphorus saturable absorber Proceedings Article
In: 2017 Opto-Electronics and Communications Conference (OECC) and Photonics Global Conference (PGC), pp. 1–3, IEEE 2017.
@inproceedings{jin2017wideband,
title = {Wideband tunable ultrafast fiber laser using blackphosphorus saturable absorber},
author = {Xinxin Jin and Guohua Hu and Meng Zhang and Yuwei Hu and Tom Albrow-Owen and Richard CT Howe and Tien-Chun Wu and Xuekun Zhu and Zheng Zheng and Tawfique Hasan},
url = {https://ieeexplore.ieee.org/abstract/document/8114937},
year = {2017},
date = {2017-01-01},
booktitle = {2017 Opto-Electronics and Communications Conference (OECC) and Photonics Global Conference (PGC)},
pages = {1--3},
organization = {IEEE},
abstract = {We demonstrate a wideband tunable, ultrafast fiber laser mode-locked by using a solution deposited and encapsulated black phosphorus (BP) saturable absorber. Stable, picosecond pulses, tunable from 1535 nm to 1565 nm are generated.},
keywords = {},
pubstate = {published},
tppubtype = {inproceedings}
}
We demonstrate a wideband tunable, ultrafast fiber laser mode-locked by using a solution deposited and encapsulated black phosphorus (BP) saturable absorber. Stable, picosecond pulses, tunable from 1535 nm to 1565 nm are generated.
2016
194.
Demetriadou, A; Lombardi, A; Mertens, J; Hess, O; Aizpurua, J; Baumberg, J
Anomalous spectral shifts in extreme plasmonic nano-cavities Journal Article
In: 2016.
@article{demetriadouanomalousb,
title = {Anomalous spectral shifts in extreme plasmonic nano-cavities},
author = {A Demetriadou and A Lombardi and J Mertens and O Hess and J Aizpurua and J Baumberg},
url = {https://spiral.imperial.ac.uk/handle/10044/1/39277},
year = {2016},
date = {2016-09-22},
abstract = { Nanoplasmonics have the ability to confine light in sub-wavelength cavities, with recent nano-fabrication developments allowing for the realization of nanometer and sub-nanometer plasmonic cavities. We show that for such extremely small nano-cavities, the correlation between the field enhancement resonance and the radiative (far-field) resonance breaks down. This dissociation dominated the excitation and interference of higher-order modes in these nano-cavities. We discuss and demonstrate the impact of this anomalous spectral behaviour for the strong coupling of quantum emitters with plasmonic nano-cavities, where it is imperative to have nanosized cavities.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Nanoplasmonics have the ability to confine light in sub-wavelength cavities, with recent nano-fabrication developments allowing for the realization of nanometer and sub-nanometer plasmonic cavities. We show that for such extremely small nano-cavities, the correlation between the field enhancement resonance and the radiative (far-field) resonance breaks down. This dissociation dominated the excitation and interference of higher-order modes in these nano-cavities. We discuss and demonstrate the impact of this anomalous spectral behaviour for the strong coupling of quantum emitters with plasmonic nano-cavities, where it is imperative to have nanosized cavities.
193.
Diesch, S; Wolz, M; Machon, P; Sürgers, C; Belzig, W; Bernardo, A Di; Gu, Y; Linder, J; Blamire, MG; Robinson, JWA; others,
Probing Odd-Triplet Contributions to the Proximity Effect by Scanning Tunneling Spectroscopy Journal Article
In: 2016.
@article{dieschprobing,
title = {Probing Odd-Triplet Contributions to the Proximity Effect by Scanning Tunneling Spectroscopy},
author = {S Diesch and M Wolz and P Machon and C Sürgers and W Belzig and A Di Bernardo and Y Gu and J Linder and MG Blamire and JWA Robinson and others},
url = {http://semparis.lpthe.jussieu.fr/contrib/attachments/attach_11962_1.pdf},
year = {2016},
date = {2016-08-06},
abstract = {In this talk we will address the superconducting proximity effect between a superconductor (S) and a normal metal (N) linked by a spin-active interface. With the help of a low-temperature scanning tunneling microscope [1,2] we study the local density of states of trilayer systems. The first example consists of aluminum (S), the ferromagnetic insulator (FI) EuS, and the noble metal silver (N) for varying thickness of the FI. In several recent studies it has been shown that EuS acts as ferromagnetic insulator with well-defined magnetic properties down to very low thicknesses [3]. For very thin FI with dFI = 2 nm we find a strong enhancement of the induced minigap at the normal side. For intermediate thickness we observe pronounced subgap structures that vary from contact to contact. For dFI = 10 nm the spectra are in agreement with the diffusive theory for S/N structures (without FI) as confirmed in earlier studies [2]. We discuss our findings in the light of recent theories of odd-triplet contributions created by the spin-active interface [4,5,6].},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
In this talk we will address the superconducting proximity effect between a superconductor (S) and a normal metal (N) linked by a spin-active interface. With the help of a low-temperature scanning tunneling microscope [1,2] we study the local density of states of trilayer systems. The first example consists of aluminum (S), the ferromagnetic insulator (FI) EuS, and the noble metal silver (N) for varying thickness of the FI. In several recent studies it has been shown that EuS acts as ferromagnetic insulator with well-defined magnetic properties down to very low thicknesses [3]. For very thin FI with dFI = 2 nm we find a strong enhancement of the induced minigap at the normal side. For intermediate thickness we observe pronounced subgap structures that vary from contact to contact. For dFI = 10 nm the spectra are in agreement with the diffusive theory for S/N structures (without FI) as confirmed in earlier studies [2]. We discuss our findings in the light of recent theories of odd-triplet contributions created by the spin-active interface [4,5,6].