摘要
为了更好地调控等离子体氨制氢的效果,从等离子体自身入手,采用较高介电常数(37.1)的氧化锆阻挡介质,通过改变外施电压幅值和NH_(3)掺杂比例,研究大气压Ar-NH_(3)混合气体氛围放电的光电特性,利用光学发射光谱分析了放电产物的种类和代表性产物的分布规律。研究发现,随着外施电压的增加,等离子体沉积的功率逐渐增强,放电电流脉冲数目逐渐增加。较低NH_(3)比例下,亚稳态Ar原子和NH_(3)之间的彭宁反应使得放电图像表现为由汤森发展成辉光放电;而在较高NH_(3)比例下,NH_(3)对放电的淬灭作用逐渐增强,使得放电图像表现为细丝状。放电后缓慢降低电压时,较低NH_(3)比例下的辉光放电保持该放电模式熄灭,而较高NH_(3)比例下的丝状放电以单根放电柱熄灭。随着NH_(3)比例的增加,放电颜色由淡紫色转变为橙黄色,放电发射光强逐渐减弱,NH_(3)对电子的淬灭作用打破了电子产消的平衡模式,大量消耗了激发态氩原子和降低了NH产量,使得产物浓度逐渐降低。研究结果说明,一方面可以利用NH_(3)比例来调控放电模式,另一方面可通过外施电压幅值和NH_(3)比例协同控制放电产物浓度。
To better regulate the effect of plasma ammonia on hydrogen production,this work focuses on the plasma itself,and investigates the photoelectric characteristics of atmospheric discharge of Ar-NH_(3)mixture at atmospheric pressure using the barrier dielectric ZrO 2 with high dielectric constant(37.1)by changing the amplitude of applied voltage and NH_(3)doping ratio;meanwhile,the types of discharge products and distribution of representative products were further analyzed by optical emission spectroscopy(OES).It is found that the power of plasma deposition and the number of discharge current pulses are gradually increased with the increase of applied voltage.At a lower NH_(3)ratio,the Penning reaction between metastable Ar atoms and NH_(3)leads to the transition from townsend to glow discharge in the discharge image;at a higher NH_(3)ratio,the quenching effect of NH_(3)on discharge is gradually enhanced,resulting in a filamentous discharge in the discharge image.When the voltage is slowly reduced after the discharge,the glow discharge at a lower NH_(3)ratio is extinguished during keeping the discharge mode,while the filamentary discharge at a higher NH_(3)ratio is extinguished by single columnar glow discharge.As the NH_(3)ratio increases,the color of the discharge changes from light purple to orange-yellow and the optical emission intensity gradually decreases.The electron quenching effect of NH_(3)breaks the equilibrium mode of electron production and dissipation,consumes a large number of excited argon atoms and reduces the NH production,resulting in a gradual decrease in product concentration.The results show that,on one hand,the discharge mode can be regulated by NH_(3)ratio;on the other hand,the discharge product concentration can also be synergistically controlled by the applied voltage amplitude and NH_(3)ratio.
作者
赵妮
田浩
付强
常正实
ZHAO Ni;TIAN Hao;FU Qiang;CHANG Zhengshi(School of Electrical Engineering,Xi′an University of Technology,Xi′an 710048,China;School of Electrical Engineering,Xi′an Jiaotong University,Xi′an 710049,China)
出处
《石油学报（石油加工）》
EI
CAS
CSCD
北大核心
2023年第5期1162-1172,共11页
Acta Petrolei Sinica(Petroleum Processing Section)
基金
国家自然科学基金项目(12275210)
西安理工大学科研启动基金(256081905)资助。
