Article
Engineering, Electrical & Electronic
Shengliao Yan, Zhuo Chen, Yang Zhang, Yuping Yang, Yufeng Xiong, Lijie Dong
Summary: A new type of flexible polymer dielectric film was prepared by mixing f-PPTA and PVDF, which achieved a high energy-storage density and charge-discharge efficiency.
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
(2021)
Article
Materials Science, Ceramics
Tae Yeon Kim, Je Oh Choi, Gopinathan Anoop, Jaegyu Kim, Seong Min Park, Shibnath Samanta, Wooseon Choi, Young-Min Kim, Seungbum Hong, Ji Young Jo
Summary: In this study, ultrahigh energy density singlecomponent Sn-doped BaTiO3 (BTS) epitaxial thin film capacitors were successfully developed, achieving an ultrahigh energy density of 92.5 J/cm3 and energy efficiencies above 78%. These excellent results were attributed to the formation of multi-nanodomains accompanied by delayed polarization saturation, low remnant polarization, high breakdown strength, and high cycling stability. Engineering multi-nanodomains through chemical doping and epitaxial orientation is a facile approach to develop energy-efficient ultrahigh energy density capacitors.
CERAMICS INTERNATIONAL
(2021)
Article
Physics, Condensed Matter
Saleem Qashou, Atif Mossad Ali, H. H. Somaily, H. Algarn, M. M. Hafiz, M. Rashad
Summary: Chalcogenide films of Ge25Se75 were prepared by thermal evaporation, exhibiting polycrystalline nature after annealing at 340 degrees C. The high transmittance at 1000 nm suggests their potential as color filters. With an increase in annealing temperature, the optical band gap energy was found to increase, demonstrating potential for optical applications.
PHYSICA B-CONDENSED MATTER
(2022)
Article
Materials Science, Multidisciplinary
Bingyuan Ke, Xinghui Wang, Shoulin Cheng, Wangyang Li, Renming Deng, Congcong Zhang, Jie Lin, Qingshui Xie, Dong-Liang Peng
Summary: This study demonstrates an in situ plasma pretreatment method for achieving ultrahigh-power and stable thin-film electrodes using sputtered iron oxysulfide (FeOxSy) thin films. The pretreated FeOxSy thin films exhibit a remarkably high power density and stable cycling performance, thanks to their high structural integrity, perfect electrochemical reversibility, and near-surface charge exchanges.
SCIENCE CHINA-MATERIALS
(2023)
Article
Polymer Science
Jiabei Zhou, Xianzhu Zhong, Aniruddha Nag, Yang Liu, Kenji Takada, Tatsuo Kaneko
Summary: Porous polybenzimidazole derivative films were prepared using a silica template method, resulting in ultrahigh thermoresistant films with improved elongation properties and enhanced strength and hardness. Microscopic analysis confirmed the formation of pores and observed craters with swollen edges and hardened surfaces.
Article
Engineering, Electrical & Electronic
Abhishek Thakur, Mandeep Jangra, Siddhartha Dam, Shamima Hussain
Summary: Flexible composite films of PVDF with GaN as fillers were synthesized using sol-gel method, and the effects of fillers on the microstructural, morphological and dielectric properties of the films were investigated.
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
(2022)
Article
Chemistry, Multidisciplinary
Peng Wang, Lingmin Yao, Zhongbin Pan, Songhan Shi, Jinhong Yu, Yao Zhou, Yang Liu, Jinjun Liu, Qingguo Chi, Jiwei Zhai, Qing Wang
Summary: The layered polymer composite shows higher dielectric constant and improved capacitive performance under high temperatures and voltages, with lower dielectric loss compared to current polymer materials. This efficient route to dielectric polymeric materials demonstrates high energy densities and low loss over a broad temperature range.
ADVANCED MATERIALS
(2021)
Article
Polymer Science
Saliha Mutlu, Eyup Metin, Sureyya Aydin Yuksel, Ugur Bayrak, Cigdem Nuhoglu, Nergis Arsu
Summary: The study found that nanoparticles are distributed differently in solution and in polymer matrices, and the atmosphere has an impact on the shape and size of the nanoparticles. Peroxy radicals are mainly responsible for the reduction of metal ions to form metal and metal oxide nanoparticles.
EUROPEAN POLYMER JOURNAL
(2021)
Article
Materials Science, Multidisciplinary
F. F. Al-Harbi, A. A. A. Darwish, Taymour A. Hamdalla, K. F. Abd El-Rahman
Summary: In this study, a film of TlInSe2 was fabricated using a coating unit, and its morphology properties were investigated using AFM. Raman spectroscopy confirmed the similarity between the film and crystal. The results showed that the electrical conductivity of TlInSe2 thin film increased with temperature, while the AC activation energy decreased.
APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING
(2022)
Article
Chemistry, Multidisciplinary
Yifei Wang, Jierui Zhou, Antigoni C. Konstantinou, Mohamadreza Arab Baferani, Kerry Davis-Amendola, Wenqiang Gao, Yang Cao
Summary: This article introduces a sandwiched barium titanate/polyamideimide nanocomposite with reinforced interfaces through two-dimensional nanocoatings. It is demonstrated that boron nitride and montmorillonite nanocoatings can independently block and dissipate injected charges, leading to a synergetic effect on conduction loss suppression and breakdown strength enhancement. The material exhibits ultrahigh energy densities and high charge-discharge efficiency at elevated temperatures, surpassing current high-temperature polymer dielectrics.
Article
Materials Science, Multidisciplinary
Tram Nhu Hoang Tran, Tam Hoang Le, Hanh Kieu Thi Ta, Y. Thi Dang, Linh Thuy Ho Nguyen, Tan Hoang Le Doan, Chung-Kai Fang, Ing-Shouh Hwang, Thang Bach Phan, Ngoc Kim Pham
Summary: Metal-organic framework (MOF) materials, particularly zirconium (IV)carboxylate MOF (UiO-66) nanoparticles, have shown promising characteristics for resistive random-access memory, with low operation voltage, high ON/OFF ratio, excellent endurance, and long-term retention. The resistive switching behavior of UiO-66 involves contributions from multiple components, with control mechanisms including electron hopping process and formation/rupture of metal filaments. The unique properties of MOF materials, such as high porosity and large size cages, strongly influence the transport properties and switching mechanism of the device, providing insights for future research and application.
ORGANIC ELECTRONICS
(2021)
Article
Materials Science, Coatings & Films
N. Sala, M. D. Abad, J. C. Sanchez-Lopez, J. Caro, C. Colominas
Summary: Nanostructured Nb-C thin films were prepared by DC-MS and HiPIMS, with different microstructures and hardness values observed. The formation of lubricating carbon tribofilm during wear tests was observed, particularly on samples prepared by HiPIMS with higher carbon content.
SURFACE & COATINGS TECHNOLOGY
(2021)
Article
Engineering, Electrical & Electronic
Ihsan A. Aljarrah, Ahmad. A. Ahmad, A. B. Migdadi
Summary: This work successfully prepared TiO2:Nb thin films with various Li ions content and studied their crystal, morphological, optical, and electrical properties using various techniques. The introduction of Li ions was found to affect the crystal structure, transmittance, bandgap energy, refractive index, and conductivity of the thin films.
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
(2023)
Article
Materials Science, Multidisciplinary
Yufei Li, Xihui Yang, Hua Bai, Mingzhi Wang, Dashuai Cheng, Cheng Song, Zhe Yuan, Yi Liu, Zhong Shi
Summary: In this study, high-quality rare-earth iron garnet (ReIG) Tb3Fe5O12 (TbIG) thin films were successfully grown on garnet substrates with different lattice constants. The effects of film strain on the properties of TbIG films were investigated, and it was observed that the distance between magnetic atoms and the corresponding exchange interactions varied due to the strain. This work provides a method to optimize spin-orbit torque devices based on ReIG.
Article
Materials Science, Multidisciplinary
Matthias Falmbigl, Iryna S. Golovina, Christopher J. Hawley, Aleksandr Plokhikh, Or Shafir, Ilya Grinberg, Jonathan E. Spanier
Summary: This study presents an approach to increase the intrinsic tunability of compounds containing TiO6 octahedra by considering the influence of different connectivity among these octahedra. By introducing connectivity variants in nanocrystalline monoclinic BaTi2O5 thin films, a two orders of magnitude enhancement in Ti anharmonic interaction was achieved, leading to a significant decrease in dielectric constant without sacrificing tunability.
Article
Chemistry, Multidisciplinary
Shalika Parakatawella, Diptajyoti Gogoi, Poonam Deka, Yizhi Xu, Chanaka Sandaruwan, Anil C. A. Jayasundera, Mihails Arhangelskis, Ranjit Thakuria, Nadeesh M. Adassooriya
Summary: A 2:1 urea·adipic acid cocrystal was obtained in two polymorphic forms using mechanochemistry and solution crystallization. The newly synthesized cocrystal exhibited lower solubility and better sustained-release properties compared to commercially available urea.
Review
Chemistry, Multidisciplinary
Nadeesh M. Adassooriya, Sanjeev Pran Mahanta, Ranjit Thakuria
Summary: With the global challenges of increasing population and shrinking cultivation land, the expansion of global food production is essential. Nitrogen supply and management are crucial for sustainable soil fertilization and crop production, and the development of urea-based enhanced efficiency fertilizers can greatly improve nitrogen usage efficiency.
Article
Anatomy & Morphology
Felix U. Kosasih, Giorgio Divitini, Jordi Ferrer Orri, Elizabeth M. Tennyson, Gunnar Kusch, Rachel A. Oliver, Samuel D. Stranks, Caterina Ducati
Summary: Cross-sectional transmission electron microscopy is widely used for investigating organic-inorganic hybrid halide perovskite-based optoelectronic devices. However, the use of focused ion beam milling for specimen preparation can degrade the structure and composition of the perovskites. In this study, the relationship between perovskite structure and luminescence was examined to assess the quality of perovskite solar cell specimens prepared by focused ion beam milling. Hyperspectral cathodoluminescence mapping revealed that the perovskite layer remained optically active with a slight blue-shifted luminescence, indicating the preservation of the perovskite structure despite some surface amorphization. Changes in cathodoluminescence due to electron beam irradiation were also observed, emphasizing the importance of managing electron dose in electron microscopy studies of carefully prepared halide perovskite-based device specimens.
MICROSCOPY RESEARCH AND TECHNIQUE
(2022)
Article
Nanoscience & Nanotechnology
Claudius Kocher, John C. Jarman, Tongtong Zhu, Gunnar Kusch, Rachel A. Oliver, Robert A. Taylor
Summary: The study found that InGaN quantum dots grown on a nonpolar plane exhibit a lower spectral diffusion rate and longer spectral diffusion time. The lifetime of nonpolar dots is shorter than that of polar dots, but the ratio of spectral diffusion time to lifetime is more favorable for nonpolar quantum dots, increasing the chances of generating indistinguishable photons.
Article
Physics, Applied
Yaonan Hou, Menno Kappers, Chaoyuan Jin, Rachel Oliver
Summary: We report a GaN based metal-semiconductor-metal (MSM) infrared photodetector with sub-wavelength gratings on one of the working electrodes. The detector is able to detect radial polarization vortices without using external optical polarizers and exhibits faster rise and fall times.
APPLIED PHYSICS LETTERS
(2022)
Article
Physics, Applied
A. Barthel, L. Sayre, G. Kusch, R. A. Oliver, L. C. Hirst
Summary: The research highlights the benefits of integrated light management in ultra-thin devices for improved efficiency and extended lifetime through radiation resilience. Highly radiation tolerant solar cells offer significant savings in cover glass mass for space power systems.
JOURNAL OF APPLIED PHYSICS
(2022)
Article
Chemistry, Multidisciplinary
Nadeesh M. M. Adassooriya, Dilek Ozgit, Sai G. G. Shivareddy, Pritesh Hiralal, Damayanthi Dahanayake, Rachel A. A. Oliver, Gehan A. J. Amaratunga
Summary: The interface between the polymer and nanoparticle plays a crucial role in determining the dielectric properties of a polymer nanocomposite. In this study, a novel dielectric nanocomposite consisting of a high permittivity polymer and hydrogen plasma treated TiO2 nanoparticles was successfully prepared. The nanocomposites exhibited ultra-high dielectric constants and low leakage current densities. The study revealed that the polymer nanoparticle interface has a potential influence on the dielectric behavior of the composite.
Review
Physics, Applied
D. J. Binks, P. Dawson, R. A. Oliver, D. J. Wallis
Summary: LEDs based on hexagonal InGaN/GaN quantum wells are widely used for lighting applications, but their performance is limited for green and amber emission and at high drive currents. Growing quantum wells in the cubic phase is a promising alternative due to its reduced bandgap and absence of strong polarization fields. The major structural defects in cubic GaN are stacking faults, which affect the optical properties and can propagate into active layers.
APPLIED PHYSICS REVIEWS
(2022)
Article
Physics, Applied
Huixin Xiu, Simon M. Fairclough, Abhiram Gundimeda, Menno J. Kappers, David J. Wallis, Rachel A. Oliver, Martin Frentrup
Summary: Aberration-corrected scanning transmission electron microscopy techniques were used to investigate the bonding configuration of GaN in metalorganic vapor-phase epitaxy-grown cubic zincblende structure on vicinal (001) 3C-SiC/Si. The study identified the orientation and bond polarity of planar defects and found that the substrate miscut direction correlated with the crystallographic in-plane direction. The presence of hexagonal wurtzite phase on Ga-polar {111} planes and their absence on N-polar {111} planes can be tentatively explained by the preferential growth of wurtzite GaN in the Ga-polar direction.
JOURNAL OF APPLIED PHYSICS
(2023)
Article
Chemistry, Multidisciplinary
Douglas Cameron, Pierre-Marie Coulon, Simon Fairclough, Gunnar Kusch, Paul R. Edwards, Norman Susilo, Tim Wernicke, Michael Kneissl, Rachel A. Oliver, Philip A. Shields, Robert W. Martin
Summary: Existing barriers to efficient deep-UV LEDs can be overcome by utilizing threedimensional nanostructuring instead of planar growth. A hybrid top-down/bottom-up approach was used to create highly uniform AlGaN core-shell nanorods on sapphire, which showed promising features like enhanced doping and improved light extraction efficiency. The nanorods were found to have low turn-on voltages, strongly rectifying behaviors, and short carrier lifetimes, making them suitable for deep-UV-emitting LEDs.
Article
Engineering, Electrical & Electronic
Saptarsi Ghosh, Alexander M. Hinz, Martin Frentrup, Saiful Alam, David J. Wallis, Rachel A. Oliver
Summary: Compositional grading of AlGaN is widely used for the growth of low-defect crack-free GaN heterostructures on large-area silicon substrates. The mechanical and microstructural properties of the epilayers are affected by individual buffer design parameters. In this study, the stress and structural properties of GaN/graded-AlGaN/AlN/Si heterostructures were analyzed, and it was found that the AlGaN buffer and the underlying AlGaN layers play a significant role in inducing and controlling the stress in the structures.
SEMICONDUCTOR SCIENCE AND TECHNOLOGY
(2023)
Article
Physics, Applied
Yihong Ji, Martin Frentrup, Xiaotian Zhang, Jakub Pongracz, Simon M. Fairclough, Yingjun Liu, Tongtong Zhu, Rachel A. Oliver
Summary: This paper demonstrates partial strain relaxation of InGaN multiple quantum wells (MQWs) on a wafer scale by adopting a partially relaxed InGaN superlattice (SL) as the pseudo-substrate. The degree of strain relaxation in MQWs can be controlled by porosification, and the reduced strain in the pseudo-substrate can be transferred to the MQWs grown on top of it.
JOURNAL OF APPLIED PHYSICS
(2023)
Article
Physics, Applied
Aaron Wadsworth, Duleepa J. Thrimawithana, Lei Zhao, Martin Neuburger, Rachel A. Oliver, David J. Wallis
Summary: Climate change has led to the advancement of electric transportation, but the aviation industry faces difficulties with electric energy storage and propulsion. This study investigates the viability of cryogenic power electronics, specifically cryogenically cooled superconducting motors and power electronics, to enhance the effectiveness and power density of electric aircraft. The research characterizes new technologies, such as GaN and nanocrystalline materials, using novel experimental methods, demonstrating the potential for significant reductions in resistance and losses compared to traditional silicon-based systems.
SUPERCONDUCTOR SCIENCE & TECHNOLOGY
(2023)
Article
Nanoscience & Nanotechnology
R. M. Barrett, J. M. McMahon, R. Ahumada-Lazo, J. A. Alanis, P. Parkinson, S. Schulz, M. J. Kappers, R. A. Oliver, D. Binks
Summary: The internal quantum efficiency of (In, Ga)N/GaN quantum wells can exceed 90% for blue-emitting structures, but decreases for longer wavelengths and higher excitation rates, known as efficiency droop, which limits the brightness of LEDs based on such quantum wells. Various mechanisms have been proposed to explain efficiency droop, but it is still unclear which one is the most important due to the difficulty in reconciling theoretical calculations with measurements.
Article
Chemistry, Multidisciplinary
William Leigh, Soumen Mandal, Jerome A. Cuenca, David Wallis, Alexander M. Hinz, Rachel A. Oliver, Evan L. H. Thomas, Oliver Williams
Summary: The high thermal conductivity of polycrystalline diamond makes it an ideal choice for thermal management solutions in GaN devices. However, the thermal barrier at the interface between diamond and substrate limits its application. This study used in situ spectroscopic ellipsometry to monitor early-stage diamond growth on AlN and successfully developed an optical model to analyze the growth process.
