Engineering Cocatalysts onto Low-Dimensional Photocatalysts for CO₂ Reduction

Low-dimensional semiconductors are regarded as alternative architectures to achieve high-efficiency photocatalytic CO₂ reduction activity due to the unique structural and electronic properties. However, the catalytic efficiency is still limited by two factors, namely, poor surface charge separation efficiency and lack of surface-active sites for CO₂ reduction. Herein, the state-of-the-art progress of cocatalysts engineering is reviewed to ameliorate these issues, to acquire outstanding behavior. The fundamentals of cocatalysts for CO₂ photoreduction along with some noteworthy points are presented. The strategies of engineering cocatalysts for performance optimization are summarized with the emphasis on structure–performance correlations, such as component engineering, phase engineering, facet engineering, size engineering, single-atom engineering, crystallinity engineering, defect engineering, strain engineering, and interface engineering. Finally, this review is ended with an outlook on unsolved issues and perspectives over cocatalysts modified low-dimensional photocatalysts.