Clustering-Resistant Cu Single Atoms on Porous Au Nanoparticles Supported by TiO 2 for Sustainable Photoconversion of CO 2 into CH 4 .

Photocatalysts based on single atoms (SAs) modification can lead to unprecedented reactivity with recent advances. However, the deactivation of SAs-modified photocatalysts remains a critical challenge in the field of photocatalytic CO 2 reduction. In this study, we unveil the detrimental effect of CO intermediates on Cu single atoms (Cu-SAs) during photocatalytic CO 2 reduction, leading to clustering and deactivation on TiO 2 . To address this, we developed a novel Cu-SAs anchored on Au porous nanoparticles (CuAu-SAPNPs-TiO 2 ) via a vectored etching approach. This system not only enhances CH 4 production with a rate of 748.8 μmol ⋅ g -1  ⋅ h -1 and 93.1 % selectivity but also mitigates Cu-SAs clustering, maintaining stability over 7 days. This sustained high performance, despite the exceptionally high efficiency and selectivity in CH 4 production, highlights the CuAu-SAPNPs-TiO 2 overarching superior photocatalytic properties. Consequently, this work underscores the potential of tailored SAs-based systems for efficient and durable CO 2 reduction by reshaping surface adsorption dynamics and optimizing the thermodynamic behavior of the SAs.