Effect of vibrationally excited molecules on radical generation

Research Project

Project/Area Number	17H04864
Research Category	Grant-in-Aid for Young Scientists (A)
Allocation Type	Single-year Grants
Research Field	Plasma science
Research Institution	National Institute of Advanced Industrial Science and Technology
Principal Investigator	Teramoto Yoshiyuki 国立研究開発法人産業技術総合研究所, エネルギー・環境領域, 主任研究員 (00635328)
Project Period (FY)	2017-04-01 – 2020-03-31
Project Status	Completed (Fiscal Year 2019)
Budget Amount *help	¥9,100,000 (Direct Cost: ¥7,000,000、Indirect Cost: ¥2,100,000) Fiscal Year 2019: ¥1,560,000 (Direct Cost: ¥1,200,000、Indirect Cost: ¥360,000) Fiscal Year 2018: ¥1,560,000 (Direct Cost: ¥1,200,000、Indirect Cost: ¥360,000) Fiscal Year 2017: ¥5,980,000 (Direct Cost: ¥4,600,000、Indirect Cost: ¥1,380,000)
Keywords	プラズマ / レーザー計測 / ラジカル / 振動温度 / N原子 / 大気圧 / 窒素原子 / パルス / 大気圧プラズマ / ストリーマ
Outline of Final Research Achievements	Herein, we report on experimental results showing that vibrationally excited N2(v) plays an important role in producing nitrogen atoms in successive two-pulsed corona discharges. To investigate the effect of vibrationally excited N2(v) on the generation of atomic nitrogen, two pulses were generated such that their pulse intervals could be varied in a controlled manner. The resulting nitrogen atoms were measured using TALIF under atmospheric pressure N2 at different time points after each pulse. The results indicate the energy efficiency of atomic nitrogen generation in the second pulse discharge near the anode tip was a maximum of approximately 3 times that of the first pulse. Moreover, it indicates that the main generation region of atomic nitrogen in the second pulse discharge is different from that of the first pulse, although the second pulse discharge use vibrationally excited N2(v) to generate atomic nitrogen.
Academic Significance and Societal Importance of the Research Achievements	大気圧非熱平衡プラズマ中ラジカル種はその高い反応性から、幅広いプロセスで応用研究されている。一方でプラズマへ投入されたエネルギーの約70％が分子振動励起に消費されており、多くの投入エネルギーが最終的に熱に転換されている。本研究ではこの振動励起分子に蓄えられたエネルギーに着目し、それを活用することで主要ラジカルの生成効率向上を目指ことで、大気圧プラズマ技術の幅広い分野の発展に貢献するものである。