Article
Engineering, Electrical & Electronic
Keijo Jacobs, Mietek Bakowski, Per Ranstad, Hans-Peter Nee
Summary: This article investigates the performance of three differently optimized 10-kV SiC p-i-n diodes in high-power converters and compares them. The results show that using SiC diodes can reduce rectifier losses by 37%, compared to the use of Si diodes. The proportion of switching losses to total losses is low, indicating a higher possible operation frequency for SiC diodes.
IEEE TRANSACTIONS ON POWER ELECTRONICS
(2022)
Article
Chemistry, Physical
Yan Zhu, Thorsten Trupke, Ziv Hameiri
Summary: This study introduces a dynamic calibration method for injection-dependent carrier lifetime measurements, which compares lifetime measurements under quasi-steady-state and non-quasi-steady-state conditions to achieve precise calibration of experimental data and provide the net bulk doping concentration.
Article
Chemistry, Physical
Lisa Kruckemeier, Zhifa Liu, Benedikt Krogmeier, Uwe Rau, Thomas Kirchartz
Summary: Transient photoluminescence (TPL) and transient photovoltage (TPV) measurements were studied in the field of halide-perovskite photovoltaics. The experiment showed that effective monomolecular lifetimes of around 2 μs can be consistently measured in efficient methylammonium lead-iodide solar cells using both TPL and TPV methods.
ADVANCED ENERGY MATERIALS
(2021)
Article
Materials Science, Multidisciplinary
Ahmed E. Abouelregal, Hamid M. Sedighi, Abdullah H. Sofiyev
Summary: This study aims to explore the impact of semiconductor elastic materials in the thermo-photovoltaic process, by establishing a modified photothermal model to investigate various physical properties of semiconductor materials, and attempting to graphically illustrate the results using theoretical simulated results.
APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING
(2021)
Article
Chemistry, Multidisciplinary
Vladimir N. Kats, Leonid A. Shelukhin, Pavel A. Usachev, Dmitry V. Averyanov, Igor A. Karateev, Oleg E. Parfenov, Alexander N. Taldenkov, Andrey M. Tokmachev, Vyacheslav G. Storchak, Victor V. Pavlov
Summary: In this study, pump-probe measurements were conducted on EuO-based ferromagnets using a time-resolved two-color stroboscopic technique, revealing photo-induced magnetization precession. The effects of temperature, magnetic field, and polarization light helicity on the magnetization dynamics were investigated. It was found that optical spin orientation by electronic transitions triggers collective magnetization precession in these materials, suggesting potential applications in optoelectronics and spintronics.
Article
Energy & Fuels
J. Veirman, R. Varache, M. Albaric, A. Danel, B. Guo, N. Fu, Y. C. Wang
Summary: This work investigates the wafer bulk requirements for industrial amorphous/crystalline n-type silicon heterojunction cells, exploring the variations in efficiency with bulk carrier lifetime, dark resistivity, and their ratio. Validation experiments and simulations are used to determine wafer specifications for targeted efficiency, with considerations for future efficiency improvements and commercial monocrystalline wafer availability. The study also assesses the potential for stable high efficiency device production and forecasts the evolution of wafer requirements as cell efficiency approaches 25%.
SOLAR ENERGY MATERIALS AND SOLAR CELLS
(2021)
Article
Engineering, Electrical & Electronic
Mantu K. K. Hudait, Steven W. W. Johnston, Manash R. R. Das, Sengunthar Karthikeyan, Partha P. P. Sahu, Jagat Das, Jing Zhao, Robert J. J. Bodnar, Rutwik Joshi
Summary: In this study, crystallographically oriented epitaxial Ge/AlAs heterostructures were grown and passivated with ALD Al2O3 dielectrics. The microwave photoconductive decay (mu-PCD) technique was used to evaluate carrier lifetimes at room temperature. It was found that the carrier lifetime was strongly dependent on surface orientation and surface passivation, and passivated (100)Ge and (110)Ge surfaces showed significant increase in carrier lifetime, providing a path for the development of nanoscale transistors.
ACS APPLIED ELECTRONIC MATERIALS
(2023)
Article
Materials Science, Ceramics
Biswajyoti Mohanty, J. Nayak
Summary: The band gap energy of CeO2 nanostructures limits their efficiency in visible light harvesting, but forming a heterojunction with narrow band gap semiconductors such as CdS can reduce the optical band gap and effectively separate photogenerated charge carriers. CeO2/CdS nanocomposite thin films were successfully deposited on FTO glass substrates, showing improved carrier lifetime, reduced non-radiative recombination, and enhanced electrical conductivity. These improvements in CeO2/CdS films may lead to enhanced charge transportation ability, making them suitable for photovoltaic applications as demonstrated by significant values of J(sc) and V-oc obtained from photoelectrochemical solar cell measurements.
CERAMICS INTERNATIONAL
(2021)
Article
Energy & Fuels
N. Dasilva-Villanueva, B. Arikan, H. H. Canar, D. Fuertes Marron, B. Hong, A. E. Kececi, S. K. Butuner, G. Bektas, R. Turan, C. del Canizo
Summary: The study investigates the potential efficiency of solar cells based on high-quality multicrystalline Upgraded Metallurgical Grade Silicon (UMG-Si) and explores the adoption of high-efficiency cell architectures. Results show that with optimized passivating layer configurations, UMG-Si wafers can achieve high carrier lifetimes and implied open circuit voltages, demonstrating the suitability of the material for high-efficiency cells.
SOLAR ENERGY MATERIALS AND SOLAR CELLS
(2023)
Article
Crystallography
J. Erlekampf, M. Rommel, K. Rosshirt-Lilla, B. Kallinger, P. Berwian, J. Friedrich, T. Erlbacher
Summary: The study examined the impact of substrate quality on the minority carrier lifetime in 4H-SiC bipolar devices, revealing a significant effect of substrate contamination on the lifetime of epitaxial layers and the efficiency of lifetime enhancement through thermal oxidation. The presence of a deep level named SD2 in the samples was traced back to different levels of incorporation of recombination sites from the substrate into the epitaxial layer during growth, showing a good agreement with defects caused by tungsten contamination.
JOURNAL OF CRYSTAL GROWTH
(2021)
Article
Energy & Fuels
Bernd Steinhauser, Tim Niewelt, Armin Richter, Rebekka Eberle, Martin C. Schubert
Summary: Recent advancements in surface passivation technology and wafer pretreatment have significantly improved the achievable minority charge carrier lifetime in crystalline silicon. The main limitation identified in this study is likely caused by silicon bulk recombination, possibly due to impurities. Despite these limitations, the measured lifetimes on p-type and n-type crystalline silicon wafers exceed previously reported values.
Article
Physics, Applied
Jaseela Palassery Ithikkal, Yusuke Yabara, Shoko Uto, Seiichiro Izawa, Masahiro Hiramoto
Summary: This study presents the fabrication and operation of organic photovoltaic cells with lateral junctions and separated carrier-generating and carrier-transporting layers. By inserting a carrier generating layer with strong visible absorption, a significant increase in photocurrent was observed. Increasing the number of unit cells in lateral tandem cells led to an increase in photocurrent while maintaining constant photovoltage. Compared to conventional vertical tandem cells, it is easier to adjust the number of unit cells in lateral tandem cells as there is no longer a need to adjust the photocurrent density flowing in each unit cell.
APPLIED PHYSICS EXPRESS
(2021)
Article
Physics, Applied
Shun Sasaki, Noritomo Mitsugi, Shuichi Samata, Wataru Manabe, Srikanth Gollapudi, Masanori Tsukuda, Ichiro Omura
Summary: New equations for recombination lifetime calculation based on the OCVD method were proposed, which can accurately calculate the recombination lifetime of PiN diodes with a silicon epitaxial layer, and their effectiveness was verified through experiments.
JAPANESE JOURNAL OF APPLIED PHYSICS
(2023)
Article
Energy & Fuels
Nicolas Barreau, Olivier Durand, Eugene Bertin, Antoine Letoublon, Charles Cornet, Polyxeni Tsoulka, Eric Gautron, Daniel Lincot
Summary: This study investigates the epitaxial growth of Cu(In,Ga)Se2 films (CIGSe) onto GaP/Si(001) pseudosubstrates using co-evaporation, with GaP thin layer epitaxially grown by Molecular Beam Epitaxy (MBE). Extensive structural characterization of epi-CIGSe is performed through X-ray diffraction and transmission electron microscopy, revealing strong evidence of epitaxial growth of CIGSe on (GaP/Si)(001) and the propagation of twins from the GaP/Si interface through the CIGSe/GaP interface. This research aims to pave the way for future CIGSe/GaP/Si structures for tandem solar cells with c-Si bottom cell and GaP interfacial buffer layer, facilitating high-quality CIGSe epitaxial growth as a thin film top cell absorber.
SOLAR ENERGY MATERIALS AND SOLAR CELLS
(2021)
Article
Mathematics
Ahmed E. Abouelregal, Marin Marin, Sameh Askar
Summary: This study investigates thermophotovoltaic interactions by using a new mathematical model of thermoelasticity based on the Green-Naghdi model type III. The impact of temperature and electrical elastic displacement of semiconductors in the excited thermoelectric mechanism are studied theoretically using this model. The model is applied to analyze interactions in a rotating semiconductor solid sphere subjected to a thermal shock and an externally applied magnetic field.
Article
Public, Environmental & Occupational Health
Allyson J. Gallant, Paul Flowers, Karen Deakin, Nicola Cogan, Susan Rasmussen, David Young, Lynn Williams
Summary: This study aimed to enhance influenza vaccination uptake among adults with chronic respiratory conditions by using the Behaviour Change Wheel (BCW) to specify intervention content. The study identified barriers and enablers to vaccination through focus groups, interviews, and surveys. Factors such as perceptions of vaccine side effects, time constraints, and fear of needles were found to be common barriers, while enablers included protection from influenza, reminders, and support from others. Based on the findings, the study proposed a suite of multi-level intervention components involving diverse actors, recipients, and settings to enhance vaccination uptake.
PSYCHOLOGY & HEALTH
(2023)
Article
Pediatrics
Elizabeth M. A. Henderson, David Tappin, David Young, Donata Favretto, Helen Mactier
Summary: This study aimed to examine the correlation between postnatal maternal self-report of alcohol consumption during pregnancy and PEth concentration measured from dried blood spot (DBS) obtained on day 5 of life. However, the study found that PEth concentration measured from DBS obtained on day 5 of life does not reliably identify modest prenatal alcohol exposure (PAE) after 36 weeks' gestation from maternal self-report.
ARCHIVES OF DISEASE IN CHILDHOOD
(2023)
Article
Chemistry, Organic
Da-Liang Zhu, Jie Li, Qi Wu, Yanqing Wang, David J. Young, Hong-Xi Li
Summary: The efficient etherification of alcohols with aryl bromides can be promoted by sodium tert-butoxide at room temperature. This simple procedure offers a practical pathway to aryl alkyl ethers in good yields without the need for any transition metal species.
SYNTHESIS-STUTTGART
(2023)
Article
Chemistry, Multidisciplinary
Jixian Wang, Lei Li, Shan Jiang, David J. Young, Zhi-Gang Ren, Hong-Xi Li
Summary: This study presents a series of SH-group-functionalized covalent organic frameworks (COFs) as prospective photoactive materials for photocatalytic hydrogen evolution. The use of nickel thiolate as a cocatalyst significantly enhances the hydrogen evolution rate.
Article
Chemistry, Inorganic & Nuclear
Pin-Pin Ma, Zhi-Min Hao, Pan Wang, Wen-Hua Zhang, David J. Young
Summary: trans-[Ni(pdm)(2)](2+) (pdm = 2-pyridinemethanol) is a reliable synthon for constructing isoreticular metal-organic frameworks (MOFs) of linear dicarboxylates. Three one-dimensional MOFs with identical connectivity were synthesized using this synthon, and they exhibited different crystal packing patterns in the solid state.
JOURNAL OF SOLID STATE CHEMISTRY
(2023)
Article
Biochemistry & Molecular Biology
Wei Yang, Shengnan Hu, Yuwei Wang, Sisi Yan, Xiang-Qian Cao, Hong-Xi Li, David James Young, Zhi-Gang Ren
Summary: A new Ag/Cu bimetallic cluster exhibited strong phosphorescent emission at 644 nm and red-shifted emission at 678 nm upon removal of coordinated EtOH molecules. The structure and emission of the cluster were restored on exposure to EtOH vapor. The cluster also showed vapor-chromic phosphorescent response to common organic solvent vapors and a reusable PMMA film was developed as a visible sensor for MeCN.
Article
Biochemistry & Molecular Biology
Qing Li, Bo-Wei Xu, Yi-Ming Zou, Ru-Jie Niu, Jin-Xiang Chen, Wen-Hua Zhang, David James. Young
Summary: In this study, nanoscale two-dimensional Fe-II- and Co-II-based metal-organic frameworks (NMOFs) were shown to have an anticancer effect in the tumor microenvironment. These NMOFs can catalyze the production of hydroxyl radicals (center dot OH) and O-2 in the presence of H2O2, and consume O-2 to produce singlet oxygen (O-1(2)) through photodynamic therapy. Both center dot OH and O-1(2) are reactive oxygen species (ROS) that inhibit cancer cell proliferation.
Article
Biochemistry & Molecular Biology
Kiyoshi Fujisawa, Yui Kobayashi, Mitsuki Okano, Ryota Iwabuchi, Shiori Kondo, David James Young
Summary: Coordination polymers of transition metal ions, such as silver(I), are important in coordination chemistry. Silver(I) coordination polymers are often insoluble in common solvents, making it difficult to analyze them in solution. However, by using a tetramethyl-substituted bipyrazole ligand, we have synthesized more soluble silver(I) complexes with coordinated ions CF3CO2- and CF3SO3-. We determined the structures of these complexes and studied their solution behavior using various spectroscopic techniques.
Article
Chemistry, Organic
Da-Liang Zhu, Haoyu Wen, Qi Wu, Jie Li, David J. Young, Yanqing Wang, Hong-Xi Li
Summary: 3-Thiocyanated indoles were synthesized by a mild and efficient light-induced cross-coupling reaction between indoles and NH4SCN without the need for a catalyst. This method, which utilizes oxygen as the terminal oxidant and exhibits good functional group tolerance, was performed on a gram scale.
Article
Chemistry, Inorganic & Nuclear
Kiyoshi Fujisawa, Aoba Yamada, Moeka Koyama, David James Young
Summary: Tridentate, planar nitrogen containing ligands based on pyridine and pyrazoles were synthesized and their solid-state structures were analyzed. Copper(II) chlorido and trifluoromethanesulfonato complexes were formed with these ligands and their coordination geometries were studied. The UV-Vis spectra of the complexes showed pi-pi* transition band red-shift and d-d transition bands at similar energy, indicating structural changes in the solution-state. EPR spectroscopy supported the findings.
INORGANICA CHIMICA ACTA
(2023)
Article
Chemistry, Organic
Da-Liang Zhu, Jie Li, David James Young, Yanqing Wang, Hong-Xi Li
Summary: This paper presents a mild strategy for aminating aryl halides with anilines using dual photoredox and nickel catalysis. Thioxanthen-9-one, an inexpensive and readily available compound, greatly enhanced this cross-coupling reaction, yielding a diverse range of diarylamines in good yields (41-93%) at room temperature. The reaction could be performed under compact fluorescent lamp light or sunlight and was tolerant of various functional groups. It was successfully applied to the synthesis of natural products and drug molecules, even at a gram-scale. The mechanism involves several steps including oxidative addition, transmetalation, energy transfer, and reductive elimination.
ORGANIC CHEMISTRY FRONTIERS
(2023)
Article
Chemistry, Inorganic & Nuclear
You-Hui Zhao, Hai-Yan Li, David James Young, Xiangqian Cao, Da-Liang Zhu, Zhi-Gang Ren, Hong-Xi Li
Summary: Earth-abundant copper(I) coordination complexes have been developed as visible-light photocatalysts for the intermolecular atom-transfer radical addition reactions. Four heteroleptic bis-chelate Cu(I) complexes were synthesized and showed broad absorption in the visible spectrum. These complexes facilitated efficient reactions with CBr4, CCl3Br, and CHI3, yielding high product yields up to 91%. The substitution on the phpz ligand had a significant impact on the absorption, emission, redox potential, and photocatalytic activity.
DALTON TRANSACTIONS
(2023)
Article
Chemistry, Multidisciplinary
Zhi-Hao Zhang, Jia-Lu Ge, Yan Li, Qing Li, Pin-Pin Ma, Xiao-Yan Tang, Wen-Hua Zhang, David J. Young
Summary: Developing porous materials for efficient capture of I-2 is important for the sequestration and storage of radioactive iodine towards clean nuclear energy. In this study, three structurally identical two-dimensional (2D) metal-organic frameworks (MOFs) were prepared, and one of the MOFs showed the highest adsorption capacity for I-2.
Article
Biochemistry & Molecular Biology
Shan He, Yixiao Wu, Yang Zhang, Xuan Luo, Christopher T. Gibson d Jingrong Gao, Jingrong Gao, Matt Jellicoe, Hao Wang, David J. Young, Colin L. Raston
Summary: Biodegradable cellulose films derived from kombucha, processed using a vortex fluidic device, show increased mechanical strength due to intense micromixing and high shear stress of the liquid film. The films retain their biodegradability and degrade within 5 days.
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
(2023)
Article
Chemistry, Multidisciplinary
Xin-Xin Tian, Yi-Tong Liu, Yan Li, Xin-Yu Qiu, Wen-Hua Zhang, David J. Young, Qiu Chen
Summary: Introducing 2,3-dimethyl-1H-imidazol-3-ium iodide (Dmim) as a mono-dentate ligand in the preparation of ZIF-8 results in the formation of ZIF-8+ (50) and ZIF-8+ (38) with cationic 'missing linker' defects. ZIF-8+ (38) can adsorb I-125(2), and the resulting radioactive host-guest complex exhibits cytotoxicity against colon cancer cell line CT26 comparable to Na I-125(2).
CHEMICAL COMMUNICATIONS
(2022)
