Preparation and gas-sensing properties of nano-CoTiO3

This paper reports that nano-CoTiO3 powder can be used as a new type of gas -sensitive material for detecting ethanol gas. Cobalt titanate (CoTiO3) pow ders were prepared by a precipitation method. The preparation conditions we re carefully controlled. The powders obtained were characterized by X-ray d iffraction (XRD) and transmission electron microscopy (TEM). The crystallit e size of the powders calcined at 600, 700, and 800 degrees C for 2 h were 18, 22, and 40 nm, respectively. The conductance-temperature, sensitivity-o perating temperature, sensitivity-calcining temperature, and sensitivity-ga s concentration properties of the CoTiO3-based sensors were investigated. T he sensors based on nano-CoTiO3 exhibited high sensitivity, good selectivit y, and good response characteristics toward ethanol gas. (C) 2000 Elsevier Science Ltd.