Anchoring of Metal Complexes on Au 25 Nanocluster for Enhanced Photocoupled Electrocatalytic CO 2 Reduction

Atomically precise Au nanoclusters (NCs) with discrete energy levels can be used as photosensitizers for CO reduction. However, tight ligand capping of Au NCs hinders CO adsorption on its active sites. Here, a new hybrid material is obtained by anchoring of thiol functionalized terpyridine metal complexes (metal=Ru, Ni, Fe, Co) on Au NCs by ligand exchange reactions (LERs). The anchoring of Ru and Ni complexes on Au NC (Au -Ru and Au -Ni) leads to adequate CO to CO conversion for photocoupled electrocatalytic CO reduction (PECR) in terms of high selectivity, with Faradaic efficiency of CO (FE ) exceeding 90 % in a wide potential range, remarkable activity (CO production rate up to two times higher than that for pristine Au PET ) and extremely large turnover frequencies (TOFs, 63012 h at -0.97 V for Au -Ru and 69989 h at -1.07 V vs. RHE for Au -Ni). Moreover, PECR stability test indicates the excellent long-term stability of the modified NCs in contrast with pristine Au NCs. The present approach offers a novel strategy to enhance PECR activity and selectivity, as well as to improve the stability of Au NCs under light illumination, which paves the way for highly active and stable Au NCs catalysts.