Photothermal Synergistic Effect Induces Bimetallic Cooperation to Modulate Product Selectivity of CO<sub>2</sub> Reduction on Different CeO<sub>2</sub> Crystal Facets
Yuqi Ren, Yitao Si, Mingyue Du, Changjun You, Chun‐yang Zhang, Yuan‐Hao Zhu, Zhenkun Sun, Kai Huang, Maochang Liu, Lunbo Duan, Naixu Li
Abstract
Abstract Product selectivity of solar‐driven CO 2 reduction and H 2 O oxidation reactions has been successfully controlled by tuning the spatial distance between Pt/Au bimetallic active sites on different crystal facets of CeO 2 catalysts. The replacement depth of Ce atoms by monatomic Pt determines the distance between bimetallic sites, while Au clusters are deposited on the surface. This space configuration creates a favourable microenvironment for the migration of active hydrogen species (*H). The *H is generated via the activation of H 2 O on monatomic Pt sites and migrate towards Au clusters with a strong capacity for CO 2 adsorption. Under concentrated solar irradiation, selectivity of the (100) facet towards CO is 100 %, and the selectivity of the (110) and (111) facets towards CH 4 is 33.5 % and 97.6 %, respectively. Notably, the CH 4 yield on the (111) facet is as high as 369.4 μmol/g/h, and the solar‐to‐chemical energy efficiency of 0.23 % is 33.8 times higher than that under non‐concentrated solar irradiation. The impacts of high‐density flux photon and thermal effects on carriers and *H migration at the microscale are comprehensively discussed. This study provides a new avenue for tuning the spatial distance between active sites to achieve optimal product selectivity.