Wurtzite CuGaS<sub>2</sub> with an In‐Situ‐Formed CuO Layer Photocatalyzes CO<sub>2</sub> Conversion to Ethylene with High Selectivity
Subhajit Chakraborty, Risov Das, Mohd Riyaz, Kousik Das, Ashutosh Kumar Singh, Debabrata Bagchi, C. P. Vinod, Sebastian C. Peter
Abstract
Abstract We present surface reconstruction‐induced C−C coupling whereby CO 2 is converted into ethylene. The wurtzite phase of CuGaS 2. undergoes in situ surface reconstruction, leading to the formation of a thin CuO layer over the pristine catalyst, which facilitates selective conversion of CO 2 to ethylene (C 2 H 4 ). Upon illumination, the catalyst efficiently converts CO 2 to C 2 H 4 with 75.1 % selectivity (92.7 % selectivity in terms of R electron ) and a 20.6 μmol g −1 h −1 evolution rate. Subsequent spectroscopic and microscopic studies supported by theoretical analysis revealed operando‐generated Cu 2+ , with the assistance of existing Cu + , functioning as an anchor for the generated *CO and thereby facilitating C−C coupling. This study demonstrates strain‐induced in situ surface reconstruction leading to heterojunction formation, which finetunes the oxidation state of Cu and modulates the CO 2 reduction reaction pathway to selective formation of ethylene.