Low temperature in situ formation of cobalt in silicon nitride toward functional nitride nanocomposites

Abstract

This work highlights the first demonstration of a low-temperature in situ formation of Co nanocrystallites embedded within an amorphous silicon nitride matrix through careful control of the chemistry behind material design using perhydropolysilazane (PHPS) as a Si₃N₄ precursor further coordinated with CoCl₂ and ammonia as a pyrolysis atmosphere. The Co nucleation was allowed to proceed at temperatures as low as 400 °C via thermal decomposition of Co₂N pre-formed in situ by the reaction of CoCl₂ with the Si centers of PHPS at the early stage of pyrolysis (220–350 °C).