Single-Cation Catalyst: Ni Cation in Monolayered CuO for CO Oxidation
Junyi Zhou, Jinliang Pan, Jin Yu, Zhantao Peng, Zhen Xu, Qiwei Chen, Pengju Ren, Xiong Zhou, Kai Wu
Abstract
It is vital to differentiate catalytic properties between cationic and metallic single atoms at the atomic level. To achieve this, we fabricated well-defined cationic Ni atoms snugged in and metallic Ni atoms supported on monolayered CuO. The Ni cations are chemically inert for CO adsorption even at 70 K but highly active toward O2 dissociation at room temperature. The adsorbed O atoms are active to oxidize incoming CO molecules from the gas phase into CO2, which follows the Eley–Rideal mechanism, in contrast to the Mars–van Krevelen mechanism on CuO-monolayer-supported metallic Ni atoms as well as our previously reported Au and Pt model catalysts. This study helps understand the chemistry of a supported single-metal cation, which is of great importance in heterogeneous catalysis.