Tetragonal-phase BaTiO 3 powders of particle size 370 nm were synthesized by microwave sintering at 850 °C. The raw materials were BaCO 3 , TiO 2 , and alanine. SiC microspheres were used as microwave conductors. The effects of the holding time, sintering aids, and SiC addition on the preparation of BaTiO 3 were investigated. The results indicate that the addition of SiC as a microwave acceptor leads to formation of microwave micro-regions. This enables uniform heating of the raw materials and decreases the calcination temperature needed to obtain BaTiO 3 . Alanine coordinates with Ba, and this loosens the metal–CO 3 bond and promotes separation of CO 2 , decreases the BaCO 3 decomposition temperature, and provides a higher nucleation site density. It gives an idea about the microwave solid-state synthesis of BaTiO 3 powder.
Jun Ma,Nan Wu,Shi-an Sun,Ting Yao,Gong-yi Li,Tian-jiao Hu,Yi-he Li,Xiao-dong Li
Graphical Stack it up ! Vertically aligned N-doped graphene rooted on SiC microspheres (NG on SiC) is prepared by precursor pyrolysis by using a lab-made continuous preparation system. The use of acetonitrile as a raw material promotes the lateral dimensions and improves the graphitization degree of NG on SiC significantly. The metal-free carbocatalyst NG on SiC is an effective and selective oxidation catalyst towards targeted C−H bond activation of ethylbenzene. Vertically aligned N-doped graphene rooted on SiC microspheres (NG on SiC) is prepared by precursor pyrolysis. One of the raw materials, acetonitrile, has three important effects that could facilitate the N-doping process effectively, promote the lateral dimensions and improve the graphitization degree of NG on SiC significantly. The metal-free carbocatalyst NG on SiC is an effective and selective oxidation catalyst towards targeted C−H bond activation of ethylbenzene. The unique nanostructure of NG on SiC is composed of predispersed graphene, which is expected to avoid harmful agglomeration during preparation, storage, transportation, and applications.
危险品化学品经营许可证（带存储）