Synthesis of Silver Nanoparticles from Silver Closo-Dodecaborate Film for Enhanced Hydrogen Evolution

The icosahedral closo dodecaborate cluster [B₁₂H₁₂]^2- is gaining increasing interest due to its unique properties including the ease of functionalization, 3D aromaticity, and formation of metal salts with high ion conductivity. In this work, simple and effective preparation of silver closo dodecaborte (Ag₂B₁₂H₁₂) films is reported by an electrochemical route. The size of the Ag₂B₁₂H₁₂ particles in the films can be tuned from nanometers to micrometers by varying the electrochemical parameters. Ag nanoclusters with controllable sizes are successfully generated via electrochemical reduction reactions or thermal anneal of the Ag₂B₁₂H₁₂ films. When tested for hydrogen evolution reaction (HER) in an acidic solution, the as-prepared Ag nanoparticles deliver a current density of 10 mA cm^-2 at 376 mV overpotential. This research sheds light on a new synthesis of [B₁₂H₁₂]^2- based thin films, the generation of metal nano-powders, and their application in HER or other applications.