Plasma Sources Science and Technology最新文献_第8页

Concentration measurements of atomic nitrogen in an atmospheric-pressure RF plasma jet using a picosecond TALIF. 使用皮秒 TALIF 测量大气压射频等离子体射流中的原子氮浓度。

Plasma Sources Science and Technology Pub Date : 2024-01-22 DOI: 10.1088/1361-6595/ad211a

W. Khan, Pavel Dvorak, N. Bolouki, M. Mrkvičková

引用次数: 0

Kinetic model of grating-like DBD fed with flowing humid air 以流动湿空气为原料的栅格状 DBD 动力学模型

Plasma Sources Science and Technology Pub Date : 2024-01-22 DOI: 10.1088/1361-6595/ad2119

Liyang Zhang, Zhigang Liu, Yuntao Guo, Jinbao Liu, Kai Wang, Haiyun Luo, Yangyang Fu

{"title":"Kinetic model of grating-like DBD fed with flowing humid air","authors":"Liyang Zhang, Zhigang Liu, Yuntao Guo, Jinbao Liu, Kai Wang, Haiyun Luo, Yangyang Fu","doi":"10.1088/1361-6595/ad2119","DOIUrl":"https://doi.org/10.1088/1361-6595/ad2119","url":null,"abstract":"\u0000 This work proposes a coupled kinetic model to capture the spatiotemporal evolution behaviors of reactive species generated by a grating-like dielectric barrier discharge (DBD) operated in flowing humid air. The coupled model incorporates a zero-dimensional (0D) discharge model for the discharge filament and a 0D kinetic model or 2D fluid model for the afterglow region. The model is experimentally validated by the ozone measurements under different airflow rates and power levels. With the pseudo-1D plug flow approximation, the spatial distribution of species obtained by the 0D afterglow model agrees well with the 2D fluid model. The kinetics of reactive oxygen and nitrogen species (RONS) in the discharge and afterglow region and the underlying pathways are analyzed. It is predicted by the model that there exists an optimal discharge power or airflow rate to acquire a maximum density of short-lived species (OH, O2(a1Δ), HO2, etc.) delivered to a given location in the afterglow region. The key factor influencing the plasma chemistry is discharge power, regardless of initial species density, and less concerned with pulse width. The proposed model provides hints for a better understanding of DBD-relevant plasma chemistry operated in ambient air.","PeriodicalId":20192,"journal":{"name":"Plasma Sources Science and Technology","volume":"77 6","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139606392","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

Spatio-temporal electric field distributions in an atmospheric plasma jet impinging on a microchannel array surface 冲击微通道阵列表面的大气等离子体射流中的时空电场分布

Plasma Sources Science and Technology Pub Date : 2024-01-22 DOI: 10.1088/1361-6595/ad2117

S. Raskar, I. V. Adamovich, K. Konina, M. Kushner

{"title":"Spatio-temporal electric field distributions in an atmospheric plasma jet impinging on a microchannel array surface","authors":"S. Raskar, I. V. Adamovich, K. Konina, M. Kushner","doi":"10.1088/1361-6595/ad2117","DOIUrl":"https://doi.org/10.1088/1361-6595/ad2117","url":null,"abstract":"\u0000 The electric field distribution in the ionization waves propagating over a microchannel array dielectric surface, with the channels either empty or filled with distilled water, is measured by ps Electric Field Induced Second Harmonic (EFISH) generation. The surface ionization wave is initiated by the atmospheric pressure N2-Ar plasma jet impinging on the surface vertically and powered by ns pulse discharge bursts. The results show that the electric field inside the microchannels, specifically its horizontal component, is enhanced by up to a factor of 2. The field enhancement region is localized within the channels. The vertical electric field inside the channels lags in time compared to the field measured at the ridges, indicating the transient reversal of the ionization wave propagation direction across the channels (toward the jet). This is consistent with the phase-locked plasma emission images and confirmed by the kinetic modeling predictions, which show that the ionization wave “jumps” over the empty channels and propagates into the channels only after the jump between the adjacent ridges. When the channels are filled with water, the wave speed increases by up to 50%, due to the higher effective dielectric constant of the surface. No evidence of a significant electric field enhancement near the dielectric surface (ceramic or water) has been detected, within the spatial resolution of the present diagnostic, ~100 μm.","PeriodicalId":20192,"journal":{"name":"Plasma Sources Science and Technology","volume":"46 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139608489","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: 1

Theoretical mechanism behind the higher efficiency of O than OH radicals in polypropylene surface modification: A molecular dynamics study 聚丙烯表面改性中 O 自由基效率高于 OH 自由基的理论机理：分子动力学研究

Plasma Sources Science and Technology Pub Date : 2024-01-22 DOI: 10.1088/1361-6595/ad2118

Hao Du, Masahiro Sato, A. Komuro, Ryo Ono

{"title":"Theoretical mechanism behind the higher efficiency of O than OH radicals in polypropylene surface modification: A molecular dynamics study","authors":"Hao Du, Masahiro Sato, A. Komuro, Ryo Ono","doi":"10.1088/1361-6595/ad2118","DOIUrl":"https://doi.org/10.1088/1361-6595/ad2118","url":null,"abstract":"\u0000 O and OH radicals are the most important reactive oxygen species (ROS) in the plasma treatment of polymer surfaces. In our previous studies, we found that the modification efficiency of polypropylene (PP) surface by O radicals was approximately four times higher than that by OH radicals. This observation contrasts with the well-established fact that the chemical reactivity of O radicals with saturated hydrocarbons (CnH2(n+1)) is 50–60 times lower than that of OH radicals. In this study, molecular dynamics (MD) simulations with a reactive force field (ReaxFF) were used to explain this contradiction. The results showed that both O and OH radicals penetrated into the bulk of PP, namely physical adsorption occurred. The surface penetration depth of O radicals was greater than that of OH radicals. Compared to the case of OH radicals, alkoxy radicals (RO·) are more readily formed on the interactions of the PP surface with O radicals. Furthermore, the β-scission (splitting the C–C bonds) of alkoxy radicals can be accelerated by the physically adsorbed O radicals, leading to earlier breakage of PP chains. The improved efficacy of surface modification of PP upon exposure to O radicals, in contrast to OH radicals, can be attributed to the distinctions observed in the above three crucial processes.","PeriodicalId":20192,"journal":{"name":"Plasma Sources Science and Technology","volume":"21 11","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139609061","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

Numerical investigation on the discharge formation in micrometer pores in structured catalyst irradiated by a helium atmospheric pressure plasma jet 关于常压氦等离子体射流辐照结构催化剂微米孔隙中放电形成的数值研究

Plasma Sources Science and Technology Pub Date : 2024-01-19 DOI: 10.1088/1361-6595/ad208f

Wenjun Ning, Hao Shang, Xueming Shen, Saikang Shen, Xiaolong Huang, Lihua Zhao, Shenli Jia

{"title":"Numerical investigation on the discharge formation in micrometer pores in structured catalyst irradiated by a helium atmospheric pressure plasma jet","authors":"Wenjun Ning, Hao Shang, Xueming Shen, Saikang Shen, Xiaolong Huang, Lihua Zhao, Shenli Jia","doi":"10.1088/1361-6595/ad208f","DOIUrl":"https://doi.org/10.1088/1361-6595/ad208f","url":null,"abstract":"\u0000 Non-thermal plasma catalysis is a promising way to achieve high efficiency in applications such as energy conversion and chemical engineering. Although synergistic effect between plasma and catalysts has been preliminarily considered as an underlying mechanism of this type of catalysis, the formation of discharges in small-size catalyst pores, which is possible a crucial factor in plasma-activated catalysis, is still not well understood. In this paper, investigations on the interactions between a helium atmospheric pressure plasma jet (APPJ) and catalysts with micrometer-size pores of different shapes and sizes are conducted with a 2D fluid model. Simulation results show that the existence of pores makes subtle difference to the APPJ by changing equivalent capacitance, indicating the potential to achieve moderate and stable APPJ-catalysts interactions. Trace of air impurity in helium can promote the discharges in catalyst pores, and thus allow discharges forming in smaller pores. In the case when a catalyst channel is too small for direct APPJ penetration, we propose a method by producing a prior discharge in a relatively large cavity to supply seed electron to ignite discharges inside the channel. The effects of channel and cavity sizes are discussed from perspectives of discharge behavior and plasma-surface interactions. This work will contribute to the preparation of structured catalysts to potentially achieve higher efficient plasma catalysis, and better understanding the physical processes in plasma-surface interactions inside micrometer pores.","PeriodicalId":20192,"journal":{"name":"Plasma Sources Science and Technology","volume":"93 7","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139612703","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

Investigation of small-fraction molecular impurities in high-pressure helium plasmas using optical plasma diagnostic methods 利用光学等离子体诊断方法研究高压氦等离子体中的小分子杂质

Plasma Sources Science and Technology Pub Date : 2024-01-16 DOI: 10.1088/1361-6595/ad1f38

K. Urabe, Minami Toyoda, Yoshinori Matsuoka, Koji Eriguchi

{"title":"Investigation of small-fraction molecular impurities in high-pressure helium plasmas using optical plasma diagnostic methods","authors":"K. Urabe, Minami Toyoda, Yoshinori Matsuoka, Koji Eriguchi","doi":"10.1088/1361-6595/ad1f38","DOIUrl":"https://doi.org/10.1088/1361-6595/ad1f38","url":null,"abstract":"\u0000 In high-pressure plasmas using gases diluted via a rare gas, small-fraction impurities in the discharge space significantly impact the basic plasma parameters and excited-species generation processes. This study investigated the behaviors of molecular impurities in a dielectric barrier discharge (DBD) generated in a flow of high-purity He gas using optical plasma diagnostics methods. The optical emission spectra obtained under various discharge conditions (pressure, flow rate, and voltage frequency) indicated the major impurity species in the He DBD as the H2O molecule, and the DBD decomposed the H2O before reaching the measurement spot. To quantitatively analyze the H2O fraction, time-resolved laser absorption spectroscopy (LAS) was performed to measure the lifetime of He metastable (Hem) atoms in the He-DBD. The H2O fraction in the He gas flow was derived from the dependence of Hem lifetime on the voltage frequency. In addition, a model was proposed to estimate the H2O fraction under various He pressure and flow rate conditions from few reference data. The procedures to perform the optical plasma diagnostics and evaluate the fraction and behaviors of H2O impurity are expected to facilitate a better understanding and control of high-pressure plasmas.","PeriodicalId":20192,"journal":{"name":"Plasma Sources Science and Technology","volume":" 5","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139619764","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 new 2D fluid-MC hybrid approach for simulating nonequilibrium atmospheric pressure plasmas: density distribution of atomic oxygen in radio-frequency plasma jets in He/O2 mixtures 模拟非平衡大气压力等离子体的新型二维流体-MC 混合方法：He/O2 混合物中射频等离子体射流的原子氧密度分布

Plasma Sources Science and Technology Pub Date : 2024-01-16 DOI: 10.1088/1361-6595/ad1f37

M. Vass, David Schulenberg, Zoltán Donkó, I. Korolov, Peter Hartmann, J. Schulze, T. Mussenbrock

{"title":"A new 2D fluid-MC hybrid approach for simulating nonequilibrium atmospheric pressure plasmas: density distribution of atomic oxygen in radio-frequency plasma jets in He/O2 mixtures","authors":"M. Vass, David Schulenberg, Zoltán Donkó, I. Korolov, Peter Hartmann, J. Schulze, T. Mussenbrock","doi":"10.1088/1361-6595/ad1f37","DOIUrl":"https://doi.org/10.1088/1361-6595/ad1f37","url":null,"abstract":"\u0000 A spatially two dimensional fluid-MC hybrid (fluid-kinetic) simulation method is developed and applied to the COST reference microplasma jet operated in helium with an oxygen admixture of 0.5%, excited by a single frequency voltage waveform with $f=13.56$~MHz and $V_{rm rms}=275$~V. The simulation approach is based on a fluid model augmented by a Monte Carlo module that generates electron impact rates for the continuity equations solved by the fluid module. This method is capable of providing the same level of accuracy as PIC/MCC simulations with an agreement within 5-10% at atmospheric pressure, while being significantly faster (with a speedup factor of 30 for serial to 50 for parallel implementation). The simulation results are compared to previous measurements of atomic oxygen densities (Steuer D et {it al.} 2021 {it J. Phys. D: Appl. Phys.} {bf 54} 355204), and show a very good agreement. It is found that the buildup and saturation of the atomic oxygen density distribution along the jet are due to the interplay of chemical and electron impact reactions as well as of the gas flow. Comparing the simulation results to that of Liu Y et {it al.} 2021 {it J. Phys. D: Appl. Phys.} {bf 54} 275204, it is inferred that fluid models where a 2-term BE solver is used, fail to describe the COST jet in an accurate manner due to the underestimation of the electron impact rates.","PeriodicalId":20192,"journal":{"name":"Plasma Sources Science and Technology","volume":" 31","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139619077","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

Low-pressure inductively coupled plasmas in hydrogen: impact of gas heating on the spatial distribution of atomic hydrogen and vibrationally excited states 氢中的低压电感耦合等离子体：气体加热对氢原子和振动激发态空间分布的影响

Plasma Sources Science and Technology Pub Date : 2024-01-15 DOI: 10.1088/1361-6595/ad1ece

Gr Smith, Paola Diomede, A. Gibson, Scott J. Doyle, V. Guerra, M. Kushner, Timo Gans, J. Dedrick

{"title":"Low-pressure inductively coupled plasmas in hydrogen: impact of gas heating on the spatial distribution of atomic hydrogen and vibrationally excited states","authors":"Gr Smith, Paola Diomede, A. Gibson, Scott J. Doyle, V. Guerra, M. Kushner, Timo Gans, J. Dedrick","doi":"10.1088/1361-6595/ad1ece","DOIUrl":"https://doi.org/10.1088/1361-6595/ad1ece","url":null,"abstract":"\u0000 Non-equilibrium inductively coupled plasmas (ICPs) operating in hydrogen are of significant interest for applications including large-area materials processing. The spatial distribution of the atomic hydrogen is of significant importance. Increasing control of spatial gas heating, which drives the formation of neutral species density gradients and the rate of gas-temperature-dependent reactions, is critical. In this study, we use 2D fluid-kinetic simulations with the Hybrid Plasma Equipment Model to investigate the spatially resolved production of atomic hydrogen in a low-pressure planar ICP operating in pure hydrogen (10 - 20 Pa or 0.075 - 0.15 Torr, 300 W). The reaction set incorporates self-consistent calculation of the spatially resolved gas temperature and 14 vibrationally excited states. We find that the formation of neutral-gas density gradients, which result from spatially non-uniform electrical power deposition at constant pressure, can drive significant variations in the vibrational distribution function and density of atomic hydrogen when gas heating is spatially resolved. This highlights the significance of spatial gas heating on the production of reactive species in relatively high-power-density plasma processing sources.","PeriodicalId":20192,"journal":{"name":"Plasma Sources Science and Technology","volume":" 9","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139622671","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

Ultralong-lasting plasma-activated water: production and control mechanisms 超长时间等离子活化水：生产和控制机制

Plasma Sources Science and Technology Pub Date : 2024-01-05 DOI: 10.1088/1361-6595/ad1b6c

Congfu Ran, Xiongfeng Zhou, Zhiyong Wang, Kun Liu, K. Ostrikov

{"title":"Ultralong-lasting plasma-activated water: production and control mechanisms","authors":"Congfu Ran, Xiongfeng Zhou, Zhiyong Wang, Kun Liu, K. Ostrikov","doi":"10.1088/1361-6595/ad1b6c","DOIUrl":"https://doi.org/10.1088/1361-6595/ad1b6c","url":null,"abstract":"\u0000 Despite the rapidly growing interest stemming from the broad-spectrum, high inactivation capacity, and environmental friendliness of the plasma-activated water (PAW), practical applications are limited because of the PAW’s short lifetime. While low-temperature storage can extend the lifetime, but the freezing and thawing processes are energy- and labor-intense and are generally not suitable for large-scale applications such as environmental and biomedical disinfection. This work addresses this issue by developing the ultra-long-life PAW at room temperature. The innovative approach is based on using DC needle-water discharges, wherein the gaseous products are blown out and absorbed separately by a gas flow. By simply adjusting the voltage and gas flow rates, two distinctive types of PAW with acidic hydrogen peroxide and nitrite as the main products are produced and separated in the discharge chamber and gas bubbling bottle. Intentional mixing of these two PAWs causes a chain chemical reaction dominated by peroxynitrite (ONOOH). This reaction can generate a variety of short-lived reactive species, thereby achieving the ultralong-lasting PAW with very stable inactivation ability. This study further demonstrates the ability to effectively control the reaction products in both chambers and provides insights into the secondary activation mechanism of short-lived reactive species stimulated by ONOOH.","PeriodicalId":20192,"journal":{"name":"Plasma Sources Science and Technology","volume":"25 22","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139383743","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

Numerical model of restrikes in gliding arc discharges 滑弧放电中再击穿的数值模型

Plasma Sources Science and Technology Pub Date : 2024-01-05 DOI: 10.1088/1361-6595/ad1b6d

Aymeric Bourlet, F. Tholin, Julien Labaune, F. Pechereau, A. Vincent‐Randonnier, Christophe O Laux

{"title":"Numerical model of restrikes in gliding arc discharges","authors":"Aymeric Bourlet, F. Tholin, Julien Labaune, F. Pechereau, A. Vincent‐Randonnier, Christophe O Laux","doi":"10.1088/1361-6595/ad1b6d","DOIUrl":"https://doi.org/10.1088/1361-6595/ad1b6d","url":null,"abstract":"\u0000 Direct current (DC) electric arcs are of particular interest because they can produce large volumes of thermal plasmas with controlled energy deposition. When such discharges are applied in a gas flow, convection displaces the top of the arc downstream while the arc roots remain attached to the electrodes, thus increasing the length of the arc over time. However, this growth is limited by a restrike phenomenon, which starts from streamers appearing in high electric field regions and shortcutting the long, stretched electric arc. From a numerical point of view, DC arcs can be efficiently simulated with a resistive magneto-hydrodynamics (MHD) model, with numerical requirements in terms of spatial and temporal discretization that are compatible with classic fluid dynamics and combustion simulations. However, arc restrikes rely on the propagation of streamer discharges that are highly non-neutral phenomena, whereas classical MHD assumes neutrality. To tackle this problem, we propose in this paper a model of restrike that can be used in an MHD approach. After describing the ideas of the model, we perform a parametric study of the input parameters to examine its influence on the discharge dynamics.","PeriodicalId":20192,"journal":{"name":"Plasma Sources Science and Technology","volume":"10 6","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139384085","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