Synthesis Characterization of Nanostructured ZnCo2O4 with High Sensitivity to CO Gas

Abstract

In this work, nanostructured ZnCo 2 O 4 was synthesized via a microwave-assisted colloidal method, and its application as gas sensor for the detection of CO was studied. Typical diffraction peaks corresponding to the cubic ZnCo 2 O 4 spinel structure were identified at calcination temperature of 500°C by X-ray powder diffraction. A high degree of porosity in the surface of the nanostructured powder of ZnCo 2 O 4 was observed by scanning electron microscopy and transmission electron microscopy, faceted nanoparticles with a pockmarked structure were clearly identified. The estimated average particle size was approximately 75 nm. The formation of ZnCo 2 O 4 material was also confirmed by Raman characterization. Pellets fabricated with nanostructured powder of ZnCo 2 O 4 were tested as sensors using CO gas at different concentrations and temperatures. A high sensitivity value of 305-300 ppm of CO was measured at 300°C, indicating that nanostructured ZnCo 2 O 4 had a high performance in the detection of CO.