Solution Synthesis of Metal Silicide Nanoparticles

Transition-metal silicides are part of an important family of intermetallic compounds, but the high-temperature reactions that are generally required to synthesize them preclude the formation of colloidal nanoparticles. Here, we show that palladium, copper, and nickel nanoparticles react with monophenylsilane in trioctylamine and squalane at 375 °C to form colloidal Pd₂Si, Cu₃Si, and Ni₂Si nanoparticles, respectively. These metal silicide nanoparticles were screened as electrocatalysts for the hydrogen evolution reaction, and Pd₂Si and Ni₂Si were identified as active catalysts that require overpotentials of −192 and −243 mV, respectively, to produce cathodic current densities of −10 mA cm<sup>–2