▎ 摘 要
In-situ surface grown pure alpha-Si3N4 microbelts have been successfully obtained by graphene oxide-assisted pyrolysis of polyvinylsilazane at 1550 degrees C under H-2/N-2 atmosphere. The alpha-Si3N4 microbelts are 10-500 mu m length, similar to 500 mu m thickness and similar to 5 mu m width with smooth surface. The surface growth mechanism of alpha-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 degrees C but also the reaction to SiC and N-2 at 1550 degrees C. GO as an additive increases the yield of alpha-Si3N4 microbelts. The photoluminescence (PL) spectra of alpha-Si3N4 microbelts contain two emission peaks at 421 nm and 441 nm at room temperature. (C) 2019 Elsevier Ltd. All rights reserved.