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) powders were prepared by a precipitation method. The preparation conditions were carefully controlled. The powders obtained were characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). The crystallite size of the powders calcined at 600, 700, and 800°C for 2 h were 18, 22, and 40 nm, respectively. The conductance–temperature, sensitivity–operating temperature, sensitivity–calcining temperature, and sensitivity–gas concentration properties of the CoTiO3-based sensors were investigated. The sensors based on nano-CoTiO3 exhibited high sensitivity, good selectivity, and good response characteristics toward ethanol gas.