Engineering Heteronuclear Dual-Metal Active Sites in Ordered Macroporous Architectures for Enhanced CH Production from CO Photoreduction.

Photocatalytic CH synthesis from CO and HO by utilizing solar energy represents a promising sustainable process, yet its efficiency remains significantly limited. Herein, we proposed a dual-engineered strategy integrating 3D ordered macroporous (3DOM) architectures with heteronuclear dual-metal active sites to synergistically promote the photocatalytic CH production. As an example, the Cu/3DOM-InO photocatalyst was synthesized by in situ incorporating Cu single atoms (Cu SAs) into 3DOM InO through a template-assisted pyrolysis process. The strong interaction between Cu SAs and InO resulted in the formation of charge-polarized Cu─In active sites along with abundant oxygen vacancies (Os). 3DOM architectures serving as special nanoreactors displayed significant advantages in promoting CO enrichment and confining key intermediates, thereby increasing *CO coverage. Meanwhile, the charge-polarized Cu─In active sites effectively mitigated electrostatic repulsion and promoted the formation of *CO + *CHO intermediates, resulting in a thermodynamically spontaneous C─C coupling step. Therefore, the Cu/3DOM-InO photocatalyst exhibited robust CO reduction to CH, achieving high CH evolution rates under various CO concentrations, including pure CO, 10% CO in Ar (simulated flue gas), and 0.04% CO in Ar (simulated air). This work offers a novel strategy for the construction of photocatalysts with tailored microstructures and specific active sites to promote the conversion of CO and HO into multicarbon products.