The effect of pressure and temperature on the synthesis of cobalt-molybdenum oxides and their characterisation is herein reported. The synthesis was performed under hydrothermal conditions without any template. It was found that the experimental conditions affect the physical properties of the CoMoO4. SEM images demonstrate that the synthesised powder is comprised of rods, and the width of the structures is about 100 nm but the length varies from about 5 mu m to less than 1 mu m. Low temperature and pressure favour the formation of longer rods. (C) 2013 Elsevier Ltd. All rights reserved.