Unveiling Active Sites and Cooperative Role of Nonthermal Plasmas and Copper-Zinc Catalysts in the Hydrogenation of CO₂ to Methanol-publication data

Methanol synthesis via nonthermal plasma (NTP) catalytic CO₂ hydrogenation offers a sustainable solution for chemical/fuel production and carbon emission reduction using renewable energy. Despite its potential, relevant mechanistic insights into the catalytic systems remain unclear. Herein, we employ advanced in situ and operando characterisation techniques to investigate NTP catalytic CO₂ hydrogenation over Cu-Zn/ZSM-5 for methanol synthesis, elucidating the active sites and cooperative roles of NTP, copper and zinc. Our findings show that Zn could enhance the dispersion and reducibility of the Cu species and form interfacial Cu-ZnO sites. The Cu-ZnO sites are crucial for methanol formation as they facilitate additional pathways for surface CO hydrogenation to methanol compared to the monometallic Cu catalyst only having the formate pathway. Importantly, no Cu-Zn alloy formation was observed, emphasizing the role of metallic Cu and Cu-ZnO interfaces in NTP catalysis. Additionally, the results also show the role of NTP in regenerating Cu and sustaining the predominantly reduced Cu state, preventing re-oxidation and ensuring stable catalytic activity. This study elucidates the active sites and cooperative roles of NTP, copper and zinc, and advances our understanding on NTP catalysis.