Modulating Copper Ladder Spacing in Copper Phenylacetylide for Enhanced Photocatalysis via Substituent Control

Copper phenylacetylide (PACu) is a promising photocatalyst due to its unique copper ladder (CL) electron transport channel, which facilitates efficient charge transfer. However, the structure-activity relationship between the CL spacing and its catalytic performance has yet to be revealed. In this study, we skillfully selected multiple substituents to regulate the CL spacing of the PACu photocatalyst. Our findings indicate that reducing the CL spacing significantly enhances carrier separation and transport efficiency, leading to improved oxygen adsorption and activation. Specifically, PACu-F demonstrated superior photocatalytic activity, achieving a 99% conversion rate in benzylamine oxidation and maintaining an excellent stability over multiple cycles. This study confirms the feasibility of tuning the CL spacing in PACu using donor/acceptor substituents to achieve a high-efficiency photocatalytic performance, offering crucial insights into the rational design of advanced photocatalysts.