射频放电等离子体中CO_2及CO_2-H_2混合气转化反应的原位研究（英文）  

In Situ Study of the Conversion Reaction of CO_2 and CO_2-H_2 Mixtures in Radio Frequency Discharge Plasma

作　　者：杨瑞龙 张笛宇 朱康伟[1] 周寰林 叶小球[1] KLEYN Aart W. 胡殷[3] 黄强[2] YANG Ruilong;ZHANG Diyu;ZHU Kangwei;ZHOU Huanlin;YE Xiaoqiu;KLEYN Aart W.;HU Yin;HUANG Qiang(Science and Technology on Surface Physics and Chemistry Laboratory, Mianyang 621900, Sichuan Province, P. R. China;China Academy of Engineering Physics, Mianyang 621900, Sichuan Province, P. R. China;Center of Interface Dynamics for Sustainability, Institute of Materials, China Academy of Engineering Physics, Chengdu 610200,P. R. China.)

机构地区：[1]表面物理与化学重点实验室,四川绵阳621900 [2]中国工程物理研究院材料研究所可持续界面动力学研究中心,成都610200 [3]中国工程物理研究院材料研究所,四川绵阳621900

出　　处：《物理化学学报》2019年第3期292-298,共7页Acta Physico-Chimica Sinica

基　　金：supported by the National Natural Science Foundation of China(21603202,51561135013);CAEP Incubation Project,China(PY2014-7-7,PY2014-7-11)~~

摘　　要：为探索CO_2气体在低温等离子体中的分解规律,开展了近室温条件下,射频等离子体中CO_2及CO_2-H_2混合气体的电离分解行为研究。反应产物通过差分四极质谱进行在线分析,并通过发射光谱对等离子体状态进行诊断。研究结果表明,在射频电场作用下二氧化碳气体迅速电离并部分分解为一氧化碳和氧气,随着射频功率升高CO_2分解率提高,而能量效率降低。氢气的加入可以显著降低CO_2分解达到平衡所需的时间,随着H_2含量的增加,二氧化碳的分解率先降低后升高,H_2的电离状态与对CO_2分解氧的消耗是导致CO_2分解率V字形变化的主要原因。Currently, worldwide attention is focused on controlling the continually increasing emissions of greenhouse gases, especially carbon dioxide. To this end, a number of investigations have been carried out to convert the carbon dioxide molecules into value-added chemicals. As carbon dioxide is thermodynamically stable, it is necessary to develop an efficient carbon dioxide utilization method for future scaled-up applications. Recently, several approaches, such as electrocatalysis, thermolysis, and non-thermal plasma, have been utilized to achieve carbon dioxide conversion. Among them, nonthermal plasma, which contains chemically active species such as high-energy electrons, ions, atoms, and excited gas molecules, has the potential to achieve high energy efficiency without catalysts near room temperature. Here, we used radio-frequency (RF) discharge plasma, which exhibits the non-thermal feature, to explore the decomposition behavior of carbon dioxide in non-thermal plasma. We studied the ionization and decomposition behaviors of CO2 and CO2-H2 mixtures in plasma at low gas pressure. The non-thermal plasma was realized by our custom-made inductively coupled RF plasma research system. The reaction products were analyzed by on-line quadrupole mass spectrometry (differentially pumped), while the plasma status was monitored using an in situ real-time optical emission spectrometer. Plasma parameters (such as the electron temperature and ion density), which can be tuned by utilizing different discharge conditions, played significant roles in the carbon dioxide dissociation process in non-thermal plasma. In this study, the conversion ratio and energy efficiency of pure carbon dioxide plasma were investigated at different values of power supply and gas flow. Subsequently, the effect of H2 on CO2 decomposition was studied with varying H2 contents. Results showed that the carbon dioxide molecules were rapidly ionized and partially decomposed into CO and oxygen in the RF field. With increasing RF power, the conversion ratio of

关 键 词：射频放电等离子体 二氧化碳 氢气 分解率 能量效率 反应平衡 

分 类 号：O646[理学—物理化学]