%0 journal article
%@ 2380-8195
%A Zeng, G.,Liu, G.,Panzeri, G.,Kim, C.,Song, C.,Alley, O.J.,Bell, A.T.,Weber, A.Z.,Toma, F.M.

%D 2025
%J ACS Energy Letters
%N 
%P 34-39 
%R doi:10.1021/acsenergylett.4c02259
%T Surface composition impacts selectivity of ZnTe photocathodes in photoelectrochemical CO2 reduction reaction
%U https://doi.org/10.1021/acsenergylett.4c02259
 
%X Light-driven reduction of CO2 into chemicals using a photoelectrochemical (PEC) approach is considered as a promising way to meet the carbon neutral target. The very top surface of the photoelectrode and semiconductor/electrolyte interface plays a pivotal role in defining the performance for PEC CO2 reduction. However, such impact remains poorly understood. Here, we report an electrodeposition-annealing route for tailoring surface composition of ZnTe photocathodes. Our work demonstrates that a Zn-rich surface on the ZnTe photocathode is essential to impact the CO2 reduction activity and selectivity. In particular, the Zn-rich surface not only facilitated the interfacial charge carrier transfer, but also acted as electrocatalyst for boosting carbon product selectivity and suppressing the hydrogen evolution reaction. This work provides a new avenue to optimize the photocathode, as well as improvement of the CO2RR performance.