Effect of graphene oxide on in-situ surface growth of pure α-Si3N4 microbelts and their blue luminescent performance

Abstract In-situ surface grown pure α-Si3N4 microbelts have been successfully obtained by graphene oxide-assisted pyrolysis of polyvinylsilazane at 1550 °C under H2/N2 atmosphere. The α-Si3N4 microbelts are 10–500 μm length, ∼500 nm thickness and ∼5 μm width with smooth surface. The surface growth mechanism of α-Si3N4 microbelts is supposed to be vapor-solid growth. GO addition promotes not only the formation of Si-O bond and free carbon at 1000 °C but also the reaction to SiC and N2 at 1550 °C. GO as an additive increases the yield of α-Si3N4 microbelts. The photoluminescence (PL) spectra of α-Si3N4 microbelts contain two emission peaks at 421 nm and 441 nm at room temperature.