Electrodeposited Silver Alloys: Screening of Alloying Elements and Related Properties and Applications

Electrodeposited silver alloys are gaining prominence as high-performance alternatives to pure silver coatings, driven by the demand for durable connectors and cost-effective catalysts, as well as by environmental and regulatory pressures to replace cyanide-based processes. This review examines recent advancements in the electrodeposition of silver alloys, focusing on the role of alloying elements in tailoring structural, mechanical, and functional properties. Alloy systems such as Ag-Cu, Ag-Ni, Ag-Pd, and Ag-W exhibit unique phase formations - ranging from solid solutions to intermetallic compounds -, significantly enhancing electroactive surface area and wear resistance. The use of alternative complexing agents (e.g., citrates, hydantoin derivatives, etc.) is highlighted as a sustainable approach to replace cyanide. In catalysis, silver alloys demonstrate improved selectivity and activity for reactions including CO₂ reduction and ethanol oxidation, while in connector applications, alloys such as Ag-W offer superior hardness and electrical contact resistance. For tungsten, induced codeposition mechanisms are discussed, emphasizing the influence of bath composition and pH. This overview underscores the potential of electrodeposited silver alloys to meet industrial challenges, balancing performance, cost, and environmental compliance.