Effect of gas components on the postdischarge temporal behavior of OH and O of a non-equilibrium atmospheric pressure plasma driven by nanosecond voltage pulses  

作　　者：王兰萍 聂兰兰 卢新培 Lanping WANG;Lanlan NIE;Xinpei LU(State Key Laboratory of Advanced Electromagnetic Engineering and Technology,School of Electrical and Electronic Engineering,Huazhong University of Science and Technology,Wuhan 430074,People’s Republic of China)

机构地区：[1]State Key Laboratory of Advanced Electromagnetic Engineering and Technology,School of Electrical and Electronic Engineering,Huazhong University of Science and Technology,Wuhan 430074,People’s Republic of China

出　　处：《Plasma Science and Technology》2024年第5期72-81,共10页等离子体科学和技术（英文版）

基　　金：supported by National Natural Science Foundation of China(Nos.52130701 and 51977096);the National Key Research and Development Program of China(No.2021YFE0114700)。

摘　　要：OH radicals and O atoms are two of the most important reactive species of non-equilibrium atmospheric pressure plasma(NAPP),which plays an important role in applications such as plasma medicine.However,experimental studies on how the gas content affects the postdischarge temporal evolutions of OH and O in the noble gas ns-NAPP are very limited.In this work,the effect of the percentages of O_(2),N_(2),and H_(2)O on the amounts of OH and O productions and their post-discharge temporal behaviors in ns-NAPP is investigated by laser-induced fluorescence(LIF)method.The results show that the productions of OH and O increase and then decrease with the increase of O_(2)percentage.Both OH and O densities reach their maximum when about 0.8%O_(2)is added.Further increase of the O_(2)concentration results in a decrease of the initial densities of both OH and O,and leads to their faster decay.The increase of N_(2)percentage also results in the increase and then decrease of the OH and O densities,but the change is smaller.Furthermore,when the H_(2)O concentration is increased from 100 to 3000 ppm,the initial OH density increases slightly,but the OH density decays much faster,while the initial density of O decreases with the increase of the H_(2)O concentration.After analysis,it is found that OH and O are mainly produced through electron collisional dissociation.O(^(1)D)is critical for OH generation.O_(3)accelerates the consumption processes of OH and O at high O_(2)percentage.The addition of H_(2)O in the NAPP considerably enhances the electronegativity,while it decreases the overall plasma reactivity,accelerates the decay of OH,and reduces the O atom density.

关 键 词：O atom OH radical post-discharge temporal behavior laser-induced fluorescence 

分 类 号：O53[理学—等离子体物理]