Article
Engineering, Electrical & Electronic
Zhiqin Zhong, Xiang Luo, Li Zhou, Sifu Hu, Liping Dai, Shuya Wang, Shaopeng Yang
Summary: In this paper, the structure of SiNx film with uneven thickness distribution was studied for the first time. A thin SiNx film in the center and gradually thicker toward the edge was obtained by introducing a quartz layer using plasma-enhanced chemical vapor deposition (PECVD). The effects of PECVD process parameters on the uneven thickness distribution of SiNx thin film were systematically studied. The film composition changing in the radial direction was also analyzed.
OPTICAL AND QUANTUM ELECTRONICS
(2023)
Article
Chemistry, Physical
Alina A. Maksimova, Alexander Uvarov, Artem Baranov, Alexander S. Gudovskikh, Dmitri A. Kudryashov, Ekaterina A. Vyacheslavova, Ivan A. Morozov, Sylvain Le Gall, Jean-Paul Kleider
Summary: Boron phosphide layers were synthesized using different methods and their electrical contact properties with silicon were investigated. Electron accumulation at the BP/Si interface was observed, which can be attributed to low doping concentration or undoped BP and Fermi level pinning at the BP/Si interface due to the presence of interface defect states. Additionally, inserting a thin i-a-Si:H layer between BP and Si improved the minority carrier lifetime and open-circuit voltage in photovoltaic applications.
ACS APPLIED ENERGY MATERIALS
(2022)
Article
Energy & Fuels
Hao Cheng, Wei Liu, Zunke Liu, Zhenhai Yang, Dian Ma, Haojiang Du, Jun Luo, Haiyang Xing, Mingdun Liao, Yuheng Zeng, Baojie Yan, Jichun Ye
Summary: We conducted a systematic study of emitter formation using PECVD system and achieved high-efficiency solar cells through process optimization.
SOLAR ENERGY MATERIALS AND SOLAR CELLS
(2022)
Article
Materials Science, Ceramics
M. Kassmi, R. Samti, W. Dimassi, M. Amlouk
Summary: This research utilizes IR examinations and ellipsometric information to study the optical behavior of hydrogenated amorphous silicon thin films arranged by RF-PECVD process, revealing the formation of different sized regions with various optical properties.
JOURNAL OF NON-CRYSTALLINE SOLIDS
(2021)
Article
Nanoscience & Nanotechnology
Prawal P. K. Agarwal, Devon Jensen, Chien-Hua Chen, Robert M. Rioux, Themis Matsoukas
Summary: The development of an in situ nonthermal plasma technology improved the oxidation and energy release of boron nanoparticles. Treatment with nonthermal hydrogen plasma and PECVD using perfluorodecalin resulted in a reduction of the surface oxide layer and formation of a passivation barrier, leading to increased metallic boron content and energy release. The PECVD coating provided excellent passivation against air and humidity for 60 days, indicating the potential benefits for nanoenergetic applications.
ACS APPLIED MATERIALS & INTERFACES
(2021)
Article
Energy & Fuels
Haojiang Du, Zunke Liu, Wei Liu, Mingjing Xiao, Na Lin, Weiguang Yang, Qingfeng Xia, Mingdun Liao, Baojie Yan, Zhenhai Yang, Yuheng Zeng, Jichun Ye
Summary: This study proposes a new method to simultaneously prepare the front-side boron emitters and the rear-side TOPCon structures through continuous plasma enhanced chemical vapor deposition and one-step high-temperature annealing. The front-side boron emitters are fabricated using a stack of nano-SiOx/B-doped a-Si:H layers as the boron source, while the rear-side TOPCon structure consists of a PANO SiOx and a nitrogen-doped a-Si:H(n(+)). The proof-of-concept TOPCon solar cells achieved a remarkable efficiency of 24.07%.
Article
Physics, Applied
W. Ravisy, M. Richard-Plouet, B. Dey, S. Bulou, P. Choquet, A. Granier, A. Goullet
Summary: The study revealed a close relationship between the crystallinity and microstructure of TiO2 thin films with film thickness, roughness, and anatase content. The critical thickness for coalescence of large polycrystalline columns varied between continuous and pulsed modes, impacting the photocatalytic activity. The use of ellipsometry to determine this coalescence thickness provides a method to evaluate the influence of process parameters on TiO2 thin film characteristics.
JOURNAL OF PHYSICS D-APPLIED PHYSICS
(2021)
Article
Chemistry, Physical
Stanislawa Kluska, Maria Jurzecka-Szymacha, Natalia Nosidlak, Piotr Dulian, Janusz Jaglarz
Summary: In this paper, the optical and thermo-optical properties of a-SiNx:H layers obtained using the PECVD technique were investigated. SiNx:H layers with different refractive indices were prepared using silane and ammonia as precursor gases. The surface morphology and chemical composition of the layers were analyzed using various methods. Spectroscopic ellipsometry was used to determine the optical indexes, thicknesses, and optical bandgap of the films. Thermo-optical studies revealed the temperature hysteresis of the optical parameters.
Article
Physics, Applied
Hisashi Yamada, Naoto Kumagai, Toshikazu Yamada, Taiki Yamamoto
Summary: The optical properties of CVD-grown hexagonal boron nitride (h-BN) and turbostratic BN (t-BN) layers on Al2O3 substrates were investigated. The results show that the DFs of the h-BN layer are stronger and sharper compared to the t-BN layer.
APPLIED PHYSICS LETTERS
(2021)
Article
Chemistry, Multidisciplinary
Jun Fan, Pei-Ting Chia, Zheng-Feng Zhang, Ming-Chung Yang, Ming-Der Su, Cheuk-Wai So
Summary: A boron analogue of vinyl cation, pyridine-stabilized N-phosphinoamidinato N-heterocyclic carbene (NHC)-diboravinyl cation 2(+), was synthesized and its reactivity and structure were studied experimentally and computationally. The positive charge on the B-B skeleton resonates with the pyridine ligand, and the activation of the pyridine substituent is achieved through the B=B double bond. The results provide insights into the reaction mechanism and properties of this boron analogue.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Materials Science, Multidisciplinary
Mariuca Gartner, Mihai Anastasescu, Hermine Stroescu, Jose Maria Calderon-Moreno, Silviu Preda, Octavian-Gabriel Simionescu, Andrei Avram, Octavian Buiu
Summary: The physical properties of nanocrystalline graphite (NCG) layers grown via plasma-enhanced chemical vapour deposition (PECVD) were analyzed in relation to their growth time. As the plasma growth time increased, the NCG layers showed increased grain size, improved crystalline structure, and better electrical properties.
Article
Nanoscience & Nanotechnology
Sukhdeep Singh, Fabian Hanning, Joel Andersson
Summary: The study found that prolonged homogenisation heat treatments significantly deteriorated the hot ductility of cast ATI 718Plus, with observed ductility deterioration being related to more extensive liquation along the grain boundaries caused by different mechanisms. The role of Nb as the solute element and the segregating effect of minor alloying elements along the grain boundaries were discussed in connection to grain boundary liquation, contributing to a better understanding of heat-affected zone liquation cracking susceptibility.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2021)
Article
Chemistry, Multidisciplinary
Ming Xu, Zhijun Wang, Zhaohui Sun, Yizhao Ouyang, Zhengwei Ding, Tao Yu, Liang Xu, Pengfei Li
Summary: This study developed a novel method for selective activation of a remote bond using a through-(hetero)arene radical transmission concept. By a metal-free [3+2] cycloaddition reaction, pyridine-substituted cyclopentanes, cyclopentenes, and bicyclo[2.1.1]hexanes that are difficult to access using known methods were synthesized. The reaction was catalyzed by a simple and inexpensive diboron(4) compound and proceeded via dearomative/rearomative processes.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Organic
Yusuke Miyamoto, Yuto Sumida, Hirohisa Ohmiya
Summary: A new type of alkylborate has been developed for radical generation through direct photoexcitation, utilizing organoboronic acids or potassium trifluoroborates as reactants. The easy availability of organoboron compounds is a key advantage, and the excited states of these borates can also function as strong reductants for various transformations.
Article
Materials Science, Ceramics
Jia Liu, Feng Shan, Chunjuan Tang, Longgang Wang, Chuanwei Liu, Hui Sun, Guanglei Guo, Lina Liu, Qiubo Hu, Xiuyun An, Ruirui Sun
Summary: Phosphorus-boron co-doped amorphous hydrogenated silicon oxide thin films containing crystalline silicon quantum dot were prepared via plasma enhanced chemical vapor deposition on a flexible substrate. The doping efficiency and film properties were effectively controlled by using helium and argon mixed dilution in the deposition process. The variation in properties of flexible P-B co-doped Si QD/a-SiOx:H thin films was studied by tuning the He/Ar flow ratio. The successful co-doping was confirmed by the redshift of photoluminescence peak, and the size and doping concentration of quantum dots were controllable by varying the He/Ar flow ratio.
JOURNAL OF NON-CRYSTALLINE SOLIDS
(2022)
Article
Environmental Sciences
Ye Eun Kim, Junwan Lim, Hyunjung Lee, Eunyoung Lee, Dong Yeong Kim, Young-Si Jun, Jong Hun Han, Sang Hyun Lee
Summary: In this study, we demonstrate the high efficiency of porous rGO-based composite spheres in water evaporation and organic pollutant adsorption. These spheres have a high light absorption capacity, which allows them to convert solar energy into heat and facilitate water evaporation. Additionally, the composite material can block UV radiation, preventing the transformation of water pollutants into harmful components.
Article
Materials Science, Multidisciplinary
Yanying Li, Xiaocang Han, Zhen Lu, Lei Ying, Xinyao Wang, Yuqiao Zeng, Yi Gao, Qing Chen, Pan Liu
Summary: Understanding phase transitions and pore formation during vapor phase dealloying (VPD) is essential for optimizing the microstructure and composition of nanoporous metals. Using a gamma-CoZn precursor alloy, researchers found a two-step dealloying process and identified the formation of a microsized porous intermediate phase and subsequent growth of nanoporous alpha-Co. By investigating the atomic-scale mechanisms using advanced microscopy techniques, the researchers discovered the preferential formation of the intermediate phase on specific crystal planes and dominant diffusion of vacancies on the {110} planes of the precursor. The insights gained from this study can provide a new approach to fine-tuning the pore structure and composition of nanoporous metals.
Article
Environmental Sciences
Byeong-Hyeon An, Tae-Gyu Lee, Tamal Tahsin Khan, Hye-Won Seo, Hyun Jin Hwang, Young -Si Jun
Summary: In this study, a simple and selective optical detection of high-concentrated Co2+ using a graphitic carbon nitride (g-CN)-based fluorescent chemosensor is reported. The fluorescent sensing performance of CNIs is evaluated through photoluminescence (PL) emission spectroscopy in a broad Co2+ concentration range. This study provides the design principle of the chemosensor suitable for the fast and accurate optical detection of Co2+ present in a broad concentration range for the hydrometallurgy of recycling waste LIBs.
Article
Chemistry, Physical
Endong Wang, Yi Gao
Summary: Utilizing small-sized fullerenes as nanoreactors, researchers have found that hydrogen and water can react to form hyperhydrogenated water (H4O) under ambient conditions. The H4O molecule rotates freely in the cavity of the cages and maintains its structure during the simulations. Theoretical analysis suggests that H4O in the fullerene possesses high thermodynamic and chemical stability, which can be explained by electron transfer between H4O and the fullerene. This study highlights the potential of utilizing fullerenes as nanoreactors to provide confinement constraints for unexpected chemistry.
JOURNAL OF PHYSICAL CHEMISTRY A
(2023)
Article
Chemistry, Multidisciplinary
Gazi A. K. M. Rafiqul Bari, Hui-Ju Kang, Tae-Gyu Lee, Hyun Jin Hwang, Byeong-Hyeon An, Hye-Won Seo, Chang Hyun Ko, Won Hi Hong, Young-Si Jun
Summary: A dual-templating strategy using molten salts and hydrogen-bonded triazine molecules has been developed to prepare high-performance porous carbon adsorbents for CO2 capture. This strategy allows for the control of pore structure and hetero-atom insertion, resulting in improved CO2 capture performance.
Article
Chemistry, Physical
Meng Zhang, Yu Han, Wenwu Xu, Beien Zhu, Yi Gao
Summary: In this study, the reshaping of Ag, Ni, and Ir metal nanoparticles under a CO atmosphere was predicted using the multiscale structure reconstruction model. The structures of Ag nanoparticles were not significantly affected by temperature in the low-pressure environment, but changed significantly in high- and low-temperature environments. Ni and Ir nanoparticles were greatly influenced by the environment due to their stronger interactions with CO. This research demonstrates the structural changes of Ag, Ni, and Ir nanoparticles under different pressures and temperatures, providing theoretical guidance for in situ experiments and the rational design of nanocatalysts.
Article
Engineering, Chemical
Jeremy May, Dipak Koirala, Forrest Dalbec, Joshua Russell, Hui Xiong, Elena Echeverria, David N. McIlroy, I. Francis Cheng
Summary: Electrochemical oxidation of GUITAR creates a superhydrophilic surface with heightened resistance to fouling, making it suitable for a variety of applications.
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
(2023)
Article
Chemistry, Inorganic & Nuclear
Yichun Wu, Liuming Yan, Yuan Qian, Yi Gao
Summary: In this study, the lowest-energy structures of W-doped Li clusters were systematically explored using global-minimum optimization and density-functional theory calculations. The structures were found to evolve from a triangle structure to a polyhedron pyramid structure, and finally to an endohedral cluster with a W atom inside. Particularly, W@Li-12 was identified as a superatom with an icosahedral structure and a significant HOMO-LUMO gap of 1.56 eV. Ab initio molecular dynamics simulations confirmed the thermal stability of this cluster. The infrared spectrum showed two vibration peaks corresponding to the bending and stretching vibrations of the tungsten-lithium bond. The UV-Vis spectrum revealed two absorption peaks at the excitation energy of 2-4 eV, indicating the characteristics of orbital electron transition. This study lays the groundwork for understanding the mechanism of Li-W alloy in Li-ion batteries.
JOURNAL OF CLUSTER SCIENCE
(2023)
Article
Physics, Condensed Matter
Babu R. Sankhi, Elena M. Echeverria, Soumya Mandal, Muhammet Annaorazov, Ritesh Sachan, David N. Mcllroy, Derek Meyers, Emrah Turgut
Summary: In this study, we investigated the impact of cobalt oxidation at the Co/AlO(x) interface in Pt/Co/AlO(x) trilayer structures on the interfacial Dzyaloshinskii-Moriya interaction (DMI). Magneto-optical imaging, hysteresis loop shift, and spin-wave spectroscopy techniques were used to quantify DMI. We also correlated the cobalt oxidation with low-temperature Hall effect measurements and x-ray photoelectron spectroscopy. Our results emphasize the importance of fully characterizing magnetic films for magnetic random access memory technologies under semiconductor processing conditions, as the magnetic interactions are critical for device performance and can be highly sensitive to oxidation and other effects.
JOURNAL OF PHYSICS-CONDENSED MATTER
(2023)
Article
Chemistry, Physical
Fei Wang, Songda Li, Ruiyang You, Zhongkang Han, Wentao Yuan, Beien Zhu, Yi Gao, Hangsheng Yang, Yong Wang
Summary: MnOx-CeO2 catalysts demonstrate significant potential in the NH3 selective catalytic reduction of NOx (NH3-SCR) reaction below 300 degrees C. Through experimental and theoretical analyses, this study reveals that electron transfer between MnOx and CeO2 induces the formation of surface oxygen vacancies on CeO2, enabling the establishment of Mn-redox and Ce-redox cycles for the activation of NH3 and O2, respectively, thereby enhancing the catalytic performance at low temperatures. This work provides a mechanistic understanding of the synergy between MnOx and CeO2, which can guide the rational design of low-temperature NH3-SCR catalysts.
APPLIED SURFACE SCIENCE
(2023)
Article
Chemistry, Physical
Yiyang Liu, Hongliang Bao, Jinrong Yang, Xiao-Bin Fu, Ling Han, Jing Yang, Min Ge, Zheng Jiang, Yu-Ying Huang, Yuan Qian, Jian-Qiang Wang, Yi Gao, Hong-Tao Liu
Summary: A method of high dissolution of copper in molten LiCl-KCleutectic salt is reported, which results in the formation of nanoclusters with a few atoms in the salt. These nanoclusters can be frozen and maintained for over one year. By washing the solidified salt, ligand-free subnanometer copper clusters can be obtained, enabling low-cost scaled-up preparation of metal nanoclusters for fundamental research and industrial applications.
CHEMISTRY OF MATERIALS
(2023)
Article
Chemistry, Physical
Xinyi Duan, Lei Ying, Xiao-Yan Li, Beien Zhu, Yi Gao
Summary: The catalytic activity of metal nanoparticles is influenced by the coordination environment of surface sites. In this study, Monte Carlo simulations were used to investigate the correlations between different sites on Pt nanoparticles in CO oxidation reactions. The results showed that low-coordinated sites favored CO adsorption and reaction, while oxygen mainly adsorbed on high-coordinated sites. Compared to other structures, step-terrace structures exhibited higher catalytic activity. These findings indicate that the catalytic performance is affected by the kinetic synergies between different sites, and a balance between low-coordinated and high-coordinated sites is crucial for optimizing the activity of Pt catalysts.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2023)
Article
Nanoscience & Nanotechnology
C. T. Parzyck, C. A. Pennington, W. J. I. DeBenedetti, J. Balajka, E. M. Echeverria, H. Paik, L. Moreschini, B. D. Faeth, C. Hu, J. K. Nangoi, V. Anil, T. A. Arias, M. A. Hines, D. G. Schlom, A. Galdi, K. M. Shen, J. M. Maxson
Summary: This study explores the growth conditions of CsSb thin films and demonstrates its potential as an alternative material for electron source applications, showing superior performance compared to Cs3Sb.
Article
Chemistry, Physical
Endong Wang, Yi Gao
Summary: By utilizing small-sized fullerenes as nanoreactors, researchers discovered that a highly hydrogenated water species, H4O, can be formed under ambient conditions by combining H2 and H2O. The H4O molecules rotate freely inside the fullerene cages and show high thermodynamic and chemical stability, which can be attributed to electron transfer between H4O and the fullerene. This study highlights the potential of utilizing fullerenes as nanoreactors to facilitate unexpected chemical reactions.
JOURNAL OF PHYSICAL CHEMISTRY A
(2023)
Article
Chemistry, Multidisciplinary
Xinyi Duan, Xiao-Yan Li, Beien Zhu, Yi Gao
Summary: In this study, the catalytic performance of Pt nanoparticles with changing morphology and reaction conditions was investigated using a multiscale structure reconstruction model and kinetic Monte Carlo simulation. The findings revealed that nanoparticles with more well-coordinated sites exhibit optimal activity under CO-rich conditions at higher temperatures, while nanoparticles with more low-coordination sites show optimal reactivity under O-2-rich conditions at lower temperatures.
