Electron penetration triggering interface activity of Pt-graphene for CO oxidation at room temperature
Yong Wang, Pengju Ren, Jingting Hu, Yunchuan Tu, Zhongmiao Gong, Yi Cui, Yanping Zheng, Mingshu Chen, Wujun Zhang, Chao Ma, Liang Yu, Fan Yang, Ye Wang, Xinhe Bao, Dehui Deng
Abstract
Abstract Achieving CO oxidation at room temperature is significant for gas purification but still challenging nowadays. Pt promoted by 3 d transition metals (TMs) is a promising candidate for this reaction, but TMs are prone to be deeply oxidized in an oxygen-rich atmosphere, leading to low activity. Herein we report a unique structure design of graphene-isolated Pt from CoNi nanoparticles (PtǀCoNi) for efficiently catalytic CO oxidation in an oxygen-rich atmosphere. CoNi alloy is protected by ultrathin graphene shell from oxidation and therefore modulates the electronic property of Pt-graphene interface via electron penetration effect. This catalyst can achieve near 100% CO conversion at room temperature, while there are limited conversions over Pt/C and Pt/CoNiO x catalysts. Experiments and theoretical calculations indicate that CO will saturate Pt sites, but O 2 can adsorb at the Pt-graphene interface without competing with CO, which facilitate the O 2 activation and the subsequent surface reaction. This graphene-isolated system is distinct from the classical metal-metal oxide interface for catalysis, and it provides a new thought for the design of heterogeneous catalysts.