Effect of Zn Doping on Structure and Electrical Properties in Co₃O₄/Zn Nanocomposites with Different Morphology

Abstract

Two different comparatively simple methods were used to synthesize Co3O4/Zn nanocomposites in the form of nanoparticles and nanofibers with a Zn content of 0 to 33 mol%. It is shown that composites in the form of nanoparticles are a ZnxCo3‐xO4 solid solution having a spinel structure. Samples in the form of nanofibers, starting with a concentration of zinc atoms of 20 mol% and higher, in addition to the spinel structure, also contain crystalline zinc oxide ZnO. It has been established that the conductivity of composites of both types increases by 4–5 orders of magnitude upon the introduction of Zn atoms. The increase in conductivity is explained by the incorporation of zinc atoms into the crystal lattice of cobalt oxide spinel. The optimal content of zinc atoms, at which the samples have the highest conductivity, has been determined. The ability to control the conductivity of cobalt oxide Co3O4 both in the form of nanoparticles and in the form of nanofibers by introducing Zn atoms has been demonstrated. The results obtained make it possible to understand the features of electric transport in such low‐dimensional systems, and are also of interest for various practical applications, in particular, gas sensors and catalytically active materials.