Films based on cerium oxide sensitive to carbon monoxide

•CeO2 nanoparticles were synthesized by the microwave-assisted hydrothermal method.•Influences of the addition of Nd on the sensing properties.•Nanoparticles as a gas detector. This work compares the influence of adding Nd to CeO2 used in the manufacture of a gas sensor device for the detection of CO. The powders obtained by microwave assisted hydrothermal method (MAH) were characterized by X-ray diffraction (XDR) and Rietveld refinement (RR) presenting cubic fluorite structure in a space group of Fm3m. Transmission electronic microscopy (TEM) images showed that nanoparticles became polyhedric decreasing an average particle size from 7.8 to 4.7 nm adding Nd, and a domain of the surface (111), and (200) for sample non-doped and Nd-doped, respectively. Sample Nd-doped showed better sensitivity to CO, observed at 380 °C and had a response time of 26 s that made the ceramics as promises for the manufacture of selective sensor CO.