Journal of Physics D: Applied Physics最新文献_第8页

Nanosecond pulsed gliding arc plasma for ammonia synthesis: Better insight from discharge mode and electron temperature 用于合成氨的纳秒脉冲滑弧等离子体：从放电模式和电子温度更好地洞察

Journal of Physics D: Applied Physics Pub Date : 2024-07-04 DOI: 10.1088/1361-6463/ad5f3d

Xiaofang Xu, Meng Sun, Qinlong Song, Guangyi Liu, Haibao Zhang

{"title":"Nanosecond pulsed gliding arc plasma for ammonia synthesis: Better insight from discharge mode and electron temperature","authors":"Xiaofang Xu, Meng Sun, Qinlong Song, Guangyi Liu, Haibao Zhang","doi":"10.1088/1361-6463/ad5f3d","DOIUrl":"https://doi.org/10.1088/1361-6463/ad5f3d","url":null,"abstract":"\u0000 Low-temperature plasma technology is a promising technological route to achieve green and efficient ammonia synthesis at ambient temperature and pressure. In this work, a Laval nozzle type gliding arc plasma reactor was designed for the direct synthesis of ammonia from N2 and H2 discharges ignited by a high voltage nanosecond pulsed power supply to investigate the effect of different electrode gaps, pulse voltages, and VN2:VH2 on ammonia synthesis. The nanosecond pulsed plasma discharges were characterized through oscilloscope and optical emission spectroscopy (OES). The maximum rate of NH3 synthesis was 538.12 μmol•h-1 at 1.5 mm electrode gap, 16 kV peak pulse voltage, 6 kHz pulse repetition frequency, 100 ns pulse width, 100 ns pulse rising edge, 100 ns pulse falling edge, and 200 mL min-1 total gas flow rate with VN2:VH2=1:1. It was demonstrated that the discharge mode of the nanosecond pulsed gliding arc plasma can transit from a unipolar state to a bipolar state determined by the duty cycle accompanied with higher discharge power and vibrational temperature. Bipolar discharge mode is beneficial to improve the efficiency of plasma ammonia synthesis because of it can strengthen the plasma discharge and increase the vibrational temperature. The ammonia synthesis rate and N2 conversion rate increased with the increase of the discharge power and electron vibrational temperature.","PeriodicalId":507822,"journal":{"name":"Journal of Physics D: Applied Physics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-07-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141678441","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Strong antiferromagnetic exchange coupling at Gd2O3/GdFeO3 interfaces in nanoparticle ensembles 纳米粒子组合中 Gd2O3/GdFeO3 界面的强反铁磁交换耦合

Journal of Physics D: Applied Physics Pub Date : 2024-07-04 DOI: 10.1088/1361-6463/ad5f28

Muhammad Azeem, Udayan Anakha, Michal Mazur, Qaisar Abbas, A. Berezner

引用次数: 0

Nucleation of InP on Si under Micro-Crucibles at Ultra-High Vacuum using a Two-Step VLS Process 利用两步 VLS 工艺在超高真空下的微坩埚中实现硅上 InP 的成核

Journal of Physics D: Applied Physics Pub Date : 2024-07-04 DOI: 10.1088/1361-6463/ad5f38

G. R. Suwito, S. Haffouz, D. Dalacu, P. Poole, Nathaniel Quitoriano

引用次数: 0

Selective anticancer effects of plasma-activated saline in 3D tumor model co-culturing of normal cells and cancer cells 在正常细胞和癌细胞共培养的三维肿瘤模型中，血浆活性生理盐水的选择性抗癌作用

Journal of Physics D: Applied Physics Pub Date : 2024-07-04 DOI: 10.1088/1361-6463/ad5f3a

Yujing Xu, Tong Wu, Xixi Jing, Shengduo Xu, Jishen Zhang, Hao Zhang, Dingxin Liu, Li Guo, Han Xu, Xiaohu Wang, Min-Zhi Rong

{"title":"Selective anticancer effects of plasma-activated saline in 3D tumor model co-culturing of normal cells and cancer cells","authors":"Yujing Xu, Tong Wu, Xixi Jing, Shengduo Xu, Jishen Zhang, Hao Zhang, Dingxin Liu, Li Guo, Han Xu, Xiaohu Wang, Min-Zhi Rong","doi":"10.1088/1361-6463/ad5f3a","DOIUrl":"https://doi.org/10.1088/1361-6463/ad5f3a","url":null,"abstract":"\u0000 Compared with conventional 2D cell culture model, the 3D tumor model constructed in vitro is better representative of the tumor microenvironment in vivo. Here, we proposed the utilization of 3D tumor model of co-cultured cancer cells and normal cells to evaluate the selective anticancer effects of cold atmospheric plasma-activated saline (PAS), and expected to provide more precise information about PAS-tumor interactions. By cell sorting, we clarified that A375 melanoma cells and HaCaT normal skin cells purified from the 3D multicellular tumor model differ in sensitivity and responsiveness to PAS compared to the 2D culture model. And during the optimization of PAS treatment parameters, we further found that A375 cells were almost completely killed while HaCaT cells were still present in large numbers after 5 days of certain PAS treatment. Our experiment innovatively carries out the selective study of plasma technology in 3D co-culture system and provides a theoretical basis for further clinical and practical applications of PAS.","PeriodicalId":507822,"journal":{"name":"Journal of Physics D: Applied Physics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-07-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141677719","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Model of non-equilibrium near-cathode plasma layers for simulation of ignition of high-pressure arcs on cold refractory cathodes 用于模拟冷耐火阴极上高压电弧点火的非平衡近阴极等离子体层模型

Journal of Physics D: Applied Physics Pub Date : 2024-07-04 DOI: 10.1088/1361-6463/ad5f3c

D. F. Santos, N. A. Almeida, L. G. Benilova, M. Benilov

{"title":"Model of non-equilibrium near-cathode plasma layers for simulation of ignition of high-pressure arcs on cold refractory cathodes","authors":"D. F. Santos, N. A. Almeida, L. G. Benilova, M. Benilov","doi":"10.1088/1361-6463/ad5f3c","DOIUrl":"https://doi.org/10.1088/1361-6463/ad5f3c","url":null,"abstract":"\u0000 The introduction of secondary ion-electron emission into an approximate model of non-equilibrium plasma layers on hot (thermionic) cathodes of high-pressure arc discharges allows extending the model to low cathode surface temperatures. Analysis of evaluation results shows that the extended model describes glow-like discharges on cold cathodes and thermionic arc discharges on hot cathodes, as it should. In the course of glow-to-arc transitions on cold cathodes, a transient regime occurs where a hot arc spot has just formed and a significant fraction of the current still flows to the cold surface outside the spot, so that the near-cathode voltage continues to be high. The power input in the near-cathode layer is very high in this regime, and so is the electron temperature in the near-cathode region. The mean free path for collisions between the atoms and the ions in these conditions exceeds the thickness of the layer where the ion current to the cathode is generated. A new method for evaluation of the ion current under such conditions is implemented. The developed model is applicable for cathode surface temperatures below the boiling point of the cathode material and may be used for multidimensional simulations of ignition of high-current arcs on refractory cathodes.","PeriodicalId":507822,"journal":{"name":"Journal of Physics D: Applied Physics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-07-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141678726","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A hierarchal model for bacterial cell inactivation in solution by direct and indirect treatment using cold atmospheric plasmas 利用冷大气等离子体直接和间接处理溶液中细菌细胞灭活的分层模型

Journal of Physics D: Applied Physics Pub Date : 2024-07-04 DOI: 10.1088/1361-6463/ad5f3b

J. Polito, M. Kushner

{"title":"A hierarchal model for bacterial cell inactivation in solution by direct and indirect treatment using cold atmospheric plasmas","authors":"J. Polito, M. Kushner","doi":"10.1088/1361-6463/ad5f3b","DOIUrl":"https://doi.org/10.1088/1361-6463/ad5f3b","url":null,"abstract":"\u0000 Cold atmospheric plasma (CAP) devices have shown promise for a variety of plasma medical applications including wound healing and bacterial inactivation often contained in liquids. In the latter application, plasma-produced reactive oxygen and nitrogen species (RONS) interact with and damage bacterial cells, though the exact mechanism by which cell damage occurs is unclear. Computational models can help elucidate relationships between plasma-produced RONS and cell killing by enabling direct comparison between dissimilar plasma devices and by examining the effects of changing operating parameters in these devices. In biological applications, computational models of plasma-liquid interactions would be most effective in design and optimization of plasma devices if there is a corresponding prediction of the biological outcome. In this work, we propose a hierarchal model for planktonic bacterial cell inactivation by plasma produced RONS in liquid. A previously developed reaction mechanism for plasma induced modification of cysteine was extended to provide a basis for cell killing by plasma-produced RONS. Results from the model are compared to literature to provide proof of concept. Differences in time to bacterial inactivation as a function of plasma operating parameters including gas composition and plasma source configuration are discussed. Results indicate that optimizing gas-phase reactive nitrogen species (RNS) production may be key in the design of plasma devices for disinfection.","PeriodicalId":507822,"journal":{"name":"Journal of Physics D: Applied Physics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-07-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141680410","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Modulating Vacancies of Graphene Supported FeNi2S4 electrocatalysts by Radio-frequency Plasma for Overall Water Splitting 利用射频等离子体调节石墨烯支撑的 FeNi2S4 电催化剂的空位以实现整体水分离

Journal of Physics D: Applied Physics Pub Date : 2024-07-04 DOI: 10.1088/1361-6463/ad5f39

W. He, Shilin Wu, Zhaotian Zhang, Qing Yang

{"title":"Modulating Vacancies of Graphene Supported FeNi2S4 electrocatalysts by Radio-frequency Plasma for Overall Water Splitting","authors":"W. He, Shilin Wu, Zhaotian Zhang, Qing Yang","doi":"10.1088/1361-6463/ad5f39","DOIUrl":"https://doi.org/10.1088/1361-6463/ad5f39","url":null,"abstract":"\u0000 Electrolysis of water for producing hydrogen is an effective and sustainable technique to meet the continuously increasing energy demand. Nevertheless, its advancement is impeded by the inadequate catalytic efficacy for oxygen evolution reaction (OER) and hydrogen evolution reaction (HER). Vacancy defect engineering is a rational approach to simultaneously enhance the catalytic performance for both the half-reactions. However, controlling the vacancy defects is quite challenging. Here, we have employed a radio-frequency Ar plasma-assisted treatment strategy to prepare highly efficient graphene-supported FeNi2S4 bifunctional catalysts with abundant vacancies. The plasma treatment induces the formation of vacancy structures in the catalyst, modifying the free energy of reaction intermediates, surface morphology, and electronic structure as well as reducing the reaction barriers, thereby enhancing the catalytic performance. The optimized graphene-supported FeNi2S4 catalyst possesses abundant sulfur vacancies, demonstrating excellent electrocatalytic performance. At 50 mA cm-2, the overpotentials for OER and HER are 240 and 256 mV, respectively, indicating exceptional stability. Overall, this work offers valuable insights into the development of cost-effective and high-performance electrocatalysts for water electrolysis.","PeriodicalId":507822,"journal":{"name":"Journal of Physics D: Applied Physics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-07-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141679586","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Progress of GaN-Based E-mode HEMTs 基于氮化镓的 E 模式 HEMT 的研究进展

Journal of Physics D: Applied Physics Pub Date : 2024-07-02 DOI: 10.1088/1361-6463/ad5dc9

Huolin Huang, Yun Lei, Sun Nan

{"title":"Progress of GaN-Based E-mode HEMTs","authors":"Huolin Huang, Yun Lei, Sun Nan","doi":"10.1088/1361-6463/ad5dc9","DOIUrl":"https://doi.org/10.1088/1361-6463/ad5dc9","url":null,"abstract":"\u0000 With the continuous improvement of the power density and operating frequency in power conversion systems, it is necessary to develop the new power electronic products with better performances than the conventional semiconductors. As a typical representative of the wide-bandgap semiconductors, gallium nitride (GaN)-based heterostructure has unique high-density two-dimensional electron gas (2DEG) and hence can be used to fabricate the fast high electron mobility transistors (HEMTs) with low power loss. Therefore, they are considered as a promising candidate for the next-generation power devices to improve the switching efficiency and speed. Compared with the depletion mode (D-mode, also known as normally-on) devices, the enhancement-mode (E-mode, also known as normally-off) devices have the advantages of safety, energy-saving, and better circuit topology design, making them more attractive for industry applications. In this paper, the different structure schemes and fabrication technologies of the GaN-based E-mode HEMTs are reviewed and summarized. Their technical characteristics are systematically compared. The influences of material epitaxial structure, ohmic contact, material etching, field plate design, and passivation process on the device performances are discussed in detail wherein the fabrication process of the recessed-gate MIS-HEMTs are emphatically illustrated, focusing on the interface treatment technology and dielectric engineering. In addition, the complicated reliability issues and physical mechanisms in the E-mode HEMTs induced by high temperature, high voltage, and high frequency switching are introduced and discussed. Finally, the potential technical solutions are proposed and the future application fields of GaN-based E-mode HEMTs are prospected.","PeriodicalId":507822,"journal":{"name":"Journal of Physics D: Applied Physics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141685819","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Effect of Hydrogen Poisoning on p-gate AlGaN/GaN HEMTs 氢气中毒对 p 栅极 AlGaN/GaN HEMT 的影响

Journal of Physics D: Applied Physics Pub Date : 2024-07-02 DOI: 10.1088/1361-6463/ad5dca

Zhiyuan He, Liang He, Kun Jiang, Xiaoyue Duan, Yijun Shi, Xinghuan Chen, Yuan Chen, Hualong Wu, Guoguang Lu, Y. Ni

{"title":"Effect of Hydrogen Poisoning on p-gate AlGaN/GaN HEMTs","authors":"Zhiyuan He, Liang He, Kun Jiang, Xiaoyue Duan, Yijun Shi, Xinghuan Chen, Yuan Chen, Hualong Wu, Guoguang Lu, Y. Ni","doi":"10.1088/1361-6463/ad5dca","DOIUrl":"https://doi.org/10.1088/1361-6463/ad5dca","url":null,"abstract":"\u0000 In this work, we investigate the degradation behavior and mechanism of p-gate AlGaN/GaN high-electron-mobility transistors (HEMTs) for the first time under hydrogen (H2) atmosphere. The experimental results reveal significant decrease in drain-to-source current, negative drift in threshold voltage, increase in off-state gate leakage current, and deterioration of subthreshold swing in the p-gate AlGaN/GaN HEMT after H2 treatment. The degradation of the electrical parameters is considered to hydrogen poisoning phenomenon. Through secondary ion mass spectrometry and variable temperature photoluminescence spectroscopy, we observe the increase in hydrogen concentration in the p-GaN layer and the formation of electrically inactive Mg-H complexes after H2 treatment. As results, the effective hole concentration decreases and the trap density of the device increases, which are confirmed by Hall effect measurement and low-frequency noise analysis, respectively. The detrimental effect of hydrogen on p-gate AlGaN/GaN HEMTs can be attributed primarily to the compensation of Mg doping and the generation of defects.","PeriodicalId":507822,"journal":{"name":"Journal of Physics D: Applied Physics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141687107","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Temperature-dependent epitaxial evolution of carbon-free corundumα-Ga2O3 on sapphire 蓝宝石上无碳刚玉α-Ga2O3 的温度依赖性外延演化

Journal of Physics D: Applied Physics Pub Date : 2024-04-25 DOI: 10.1088/1361-6463/ad4365

Lei Dai, Jinggang Hao, Mei Cui, Yanfang Zhang, Y. Kuang, Zhengpeng Wang, F. Ren, S. Gu, J. Ye

{"title":"Temperature-dependent epitaxial evolution of carbon-free corundumα-Ga2O3 on sapphire","authors":"Lei Dai, Jinggang Hao, Mei Cui, Yanfang Zhang, Y. Kuang, Zhengpeng Wang, F. Ren, S. Gu, J. Ye","doi":"10.1088/1361-6463/ad4365","DOIUrl":"https://doi.org/10.1088/1361-6463/ad4365","url":null,"abstract":"\u0000 Unintentionally doped carbon impurities from organometallic precursors are primary sources of carrier compensation and mobility degradation in wide bandgap semiconductors, leading to lowered performance of power devices. To address this challenge, carbon-free α-Ga2O3 single crystalline thin-films were heteroepitaxially grown on sapphire substrates by using gallium inorganic precursors through mist chemical vapor deposition technique. Determined through temperature dependence of growth rates, three distinct growth regimes are identified: the surface reaction limited regime below 480°C, the mid-temperature mass-transport limited regime (480-530 °C) and the high temperature limited regime related to desorption or phase transition. With an optimized around 530 °C, the densities of screw and edge dislocations are reduced to 7.17×10^6 and 7.60×10^9 cm-2, respectively. Notably, carbon incorporation was eliminated in the α-Ga2O3 grown by inorganic GaCl3, as evidenced by the absence of carbon-related vibrational bands in Raman scattering analysis, while crystalline quality was comparable to that grown with organometallic precursors. The high solubility of GaCl3 in water is expected to enable the rapid growth of high-purity α-Ga2O3 with improved electronic performances. Keywords: ultrawide bandgap semiconductor, chemical vapor deposition, impurity contamination.","PeriodicalId":507822,"journal":{"name":"Journal of Physics D: Applied Physics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-04-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140657659","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0