Three-Phase Interface Construction on Hydrophobic Carbonaceous Catalysts for Highly Active and Selective Photocatalytic CO<sub>2</sub> Conversion
Qi-Su Huang, Chengcheng Chu, Qiuju Li, Qiong Liu, Xinru Liu, Jing Sun, Bing‐Jie Ni, Shun Mao
Abstract
The ever-increasing concern for adverse climate change has stimulated great research enthusiasm for CO 2 conversion. The photocatalytic CO 2 reduction reaction (CO 2 RR) has become one of the promising approaches to converting CO 2 into value-added fuels. However, CO 2 RR suffers from intense competition from the hydrogen evolution reaction (HER) for electrons in aqueous solution due to the limited mass transfer of CO 2 in water. In this study, we propose to construct the three-phase interface on the photocatalyst surface by decorating with a hydrophobic carbonaceous cocatalyst to achieve efficient contact of CO 2 (gas), catalyst (solid), and water (liquid). The decorated photocatalyst exhibits significantly improved CO 2 -to-CH 4 activity, and the CO 2 RR selectivity is greatly elevated from 61 to 97%. It is demonstrated that the hydrophobic cocatalyst plays a critical role in regulating the CO 2 RR performance by increasing the interfacial CO 2 concentration. Molecular dynamics simulations further reveal that the hydrophobic microenvironment is constructed by preventing the hydrogen bond formation on the carbonaceous cocatalyst surface. Overall, this study provides a general method to relieve the CO 2 mass transfer limit to accelerate the CO 2 RR in water.