| 초록 |
Atomically precise metal nanoclusters have attracted growing attention recently as promising electrocatalysts. Here, I present that the product selectivity in the electrocatalytic conversion of CO2 in aqueous media can be controlled by the core dopant of MAu24(SR)18 (M= Au, Pt), where SR is hexanethiolate. Constant potential electrolysis on electrodes modified with these nanoclusters exhibited drastically different product selectivity. That is, whereas CO was predominantly produced on Au25(SR)18 with a selectivity higher than 90 %, nearly 75 % H2 was produced on PtAu24(SR)18. Density functional theory (DFT) calculations showed that the product selectivity appears to be closely related with the adsorption energies of the reactants, i.e., CO2 and proton on the nanocluster catalyst. Highly selective and controlled production of syngas in the range of H2/CO = 1-4 was demonstrated by controlling the catalyst ratio in the mixture of Au25(SR)18 and PtAu24(SR)18 nanoclusters. |
