Enhanced NH<sub>3</sub> Synthesis from Air in a Plasma Tandem-Electrocatalysis System Using Plasma-Engraved N-Doped Defective MoS<sub>2</sub>
Jiageng Zheng, Hao Zhang, Jiabao Lv, Meng Zhang, Jieying Wan, Nick Gerrits, Angjian Wu, Bingru Lan, Weitao Wang, Shuangyin Wang, Xin Tu, Annemie Bogaerts, Xiaodong Li
Abstract
High Resolution Image Download MS PowerPoint Slide We have developed a sustainable method to produce NH 3 directly from air using a plasma tandem-electrocatalysis system that operates via the N 2 –NO x –NH 3 pathway. To efficiently reduce NO 2 – to NH 3, we propose a novel electrocatalyst consisting of defective N-doped molybdenum sulfide nanosheets on vertical graphene arrays (N-MoS 2 /VGs). We used a plasma engraving process to form the metallic 1T phase, N doping, and S vacancies in the electrocatalyst simultaneously. Our system exhibited a remarkable NH 3 production rate of 7.3 mg h –1 cm –2 at −0.53 V vs RHE, which is almost 100 times higher than the state-of-the-art electrochemical nitrogen reduction reaction and more than double that of other hybrid systems. Moreover, a low energy consumption of only 2.4 MJ mol NH 3 –1 was achieved in this study. Density functional theory calculations revealed that S vacancies and doped N atoms play a dominant role in the selective reduction of NO 2 – to NH 3 . This study opens up new avenues for efficient NH 3 production using cascade systems.