Degradation Mechanisms and Stabilization Strategies of Ag Nanoparticles and Atomically Precise Ag Nanoclusters for Electrochemical CO2 Reduction.

Ag nanoparticles (NPs) and atomically precise Ag nanoclusters (NCs) are highly promising catalysts for electrocatalytic CO2 reduction reaction (CO2RR). Ag NPs offer high electrical conductivity, cost-effectiveness, large specific surface areas, and high activity for CO production, whereas Ag NCs feature discrete electronic structures, defined compositions, and tunable core-ligand environments. However, under catalytically relevant potential and reaction conditions, Ag nanostructures are susceptible to degradation. To address the critical stability issue, recent studies have systematically investigated degradation mechanisms and proposed corresponding stabilization strategies. Herein, focusing on Ag NPs and Ag NCs, we summarize and classify their degradation mechanisms into three dominant pathways: potential-driven reconstruction, dissolution-redeposition, and three-phase interface failure. We then discuss stabilization strategies for these degradation pathways and benchmark representative Ag NP- and Ag NC-based catalysts in terms of CO Faradaic efficiency, current density, and operational durability within a stability-performance framework. By systematically analyzing these strategies, we aim to distill rational design principles for future development of highly stable and efficient Ag-based CO2RR nanocatalysts.