Ligand-controlled exposure of active sites on the Pd₁Ag₁₄ nanocluster surface to boost electrocatalytic CO₂ reduction

Advancing catalyst design requires meticulous control of nanocatalyst selectivity at the atomic level. Here, we synthesized two Pd1Ag14 nanoclusters: Pd1Ag14(PPh3)(8)(SPh(CF3)(2))(6) and Pd1Ag14(P(Ph-p-OMe)(3))(7)(SPh)(6), each with well-defined structures. Notably, in Pd1Ag14(P(Ph-p-OMe)(3))(7)(SPh)(6), the detachment of a phosphine ligand from the top silver atom facilitates the exposure of singular active sites. This exposure significantly enhances its selectivity for the electrocatalytic reduction of CO2 to CO, achieving a Faraday efficiency of 83.3% at -1.3 V, markedly surpassing the 28.1% performance at -1.2 V of Pd1Ag14(PPh3)(8)(SPh(CF3)(2))(6). This work underscores the impact of atomic-level structural manipulation on enhancing nanocatalyst performance.