Cosolvent-assisted spray pyrolysis for the generation of metal particles

Abstract

A cosolvent-assisted spray pyrolysis process was developed for the formation of phase-pure metal particles from metal salt precursors without the direct addition of hydrogen or other reducing gas. Generation of phase-pure copper and nickel particles from aqueous solutions of copper acetate, copper nitrate, and nickel nitrate over the temperature range of 450 to 1000 °C was demonstrated. Addition of ethanol as a cosolvent plays a crucial role in producing phase-pure metal powders. Results of a modeling study of ethanol decomposition kinetics suggest that cosolvent decomposition creates a strong reducing atmosphere during spray pyrolysis via in situ production of hydrogen and carbon monoxide.