Structural Disproportionation of Ag20Cu10 Highlights the Impact of Cluster Structure on Electrocatalytic Properties for CO2 reduction

Abstract

Understanding the relationship between cluster structure and catalytic performance is fundamental for developing advanced cluster-based catalysts. The interactions between SbF6⁻ ions and metal nanoclusters prove particularly significant in modulating cluster structures and properties. Herein, we report the synthesis of a novel Ag20Cu10(Dppm)2(SAdm)14Cl8 (Ag20Cu10 for short) nanocluster featuring an Ag17 barrel-like core surrounded by an Ag3Cu10(Dppm)2(SR)14Cl8 shell. Upon introduction of NaSbF6, Ag20Cu10 undergoes structural disproportionation transformation to form superatomic alloy clusters [Ag8Cu12(Dppm)4(SAdm)8Cl8]2+ (2e and Ag8Cu12 for short) and [Ag17Cu15(SAdm)13(Dppm)3Cl9]2+ (8e and Ag17Cu15 for short). These three structures share similar staples and Ag-bridging atoms, indicating core recombination while maintaining peripheral motifs during transformation. Electronic structure analysis through density functional theory (DFT) calculations reveals distinct characteristics of these Ag-Cu nanoclusters. Evaluation of their CO2 reduction reaction (CO2RR) capabilities demonstrates superior catalytic performance of Ag20Cu10 compared to Ag8Cu12 and Ag17Cu15. This enhanced performance highlights the unique structural and electronic properties of Ag₂₀Cu₁₀, which enable more effective catalytic activity during the CO₂RR process. These findings emphasize the pivotal role of SbF6⁻ in modulating Ag-Cu nanocluster structures and highlight the impact of structural features on electrocatalytic performance.