Hydrothermal synthesis and ethanol sensing properties of CeVO4 and CeVO4–CeO2 powders

CeVO4 powders with different morphologies were synthesized in basic media by surfactant-free hydrothermal process. The products were characterized by X-ray diffraction and transmission electron microscopy (TEM). From the experimental results, it has been revealed that there is an optimal pH range (pH ≤ 12.0) for the formation of pure CeVO4 and the pH plays a key role in the formation of the products of different morphologies and sizes. Increasing pH from 9 to 10 causes the morphology transformation: irregular nanoparticles → nanorods. High pH (12.0 < pH < 14.0) resulted in the formation of CeVO4–CeO2 compounds. Gas sensing behavior of CeVO4 and CeVO4–CeO2 based materials to ethanol were firstly studied. The sensors based on these materials show different response to ethanol, wherein the response is the best when using CeVO4–CeO2 compounds as material.