Solution synthesis of metal silicide nanoparticles

Area of Science:

• Materials Science
• Nanotechnology
• Electrochemistry

Background:

• Transition-metal silicides are crucial intermetallic compounds.
• Conventional synthesis methods require high temperatures, hindering nanoparticle formation.
• Colloidal nanoparticles offer unique properties for catalysis.

Purpose of the Study:

• To develop a method for synthesizing colloidal transition-metal silicide nanoparticles.
• To investigate the catalytic activity of these nanoparticles for hydrogen evolution.
• To identify efficient silicide catalysts for the hydrogen evolution reaction.

Main Methods:

• Reacting palladium, copper, and nickel nanoparticles with monophenylsilane at 375 °C in trioctylamine and squalane.
• Characterizing the resulting colloidal metal silicide nanoparticles (Pd(2)Si, Cu(3)Si, Ni(2)Si).
• Screening the nanoparticles as electrocatalysts for the hydrogen evolution reaction.

Main Results:

• Successfully synthesized colloidal Pd(2)Si, Cu(3)Si, and Ni(2)Si nanoparticles.
• Pd(2)Si and Ni(2)Si nanoparticles demonstrated activity as electrocatalysts.
• Specific overpotentials of -192 mV for Pd(2)Si and -243 mV for Ni(2)Si were required for -10 mA cm(-2) current density.

Conclusions:

• High-temperature reaction of metal nanoparticles with monophenylsilane enables colloidal silicide nanoparticle synthesis.
• Pd(2)Si and Ni(2)Si nanoparticles are effective electrocatalysts for hydrogen evolution.
• This work opens avenues for developing novel nanoparticle catalysts.