Hydrothermal synthesis and characterization of ZnCo₂O₄ nanostructures

Abstract

In this work, three types of zinc cobaltite ZnCo₂O₄ structures, namely, nanorods, nanowires, and plates, were synthesized on nickel foam using a simple hydrothermal method. The morphology and structural characteristics of the synthesized samples were studied. The grown structures can be used as a basis for enzyme-free electrochemical biosensors. A detailed analysis of a series of six samples synthesized at different Zn:Co ratios (1:1, 1:10, and 10:1) was performed using scanning electron microscopy. The results of the study of the elemental composition of ZnCo₂O₄ nanostructures synthesized by the hydrothermal method on nickel foam showed that the composition of the obtained materials correlates with the composition of the initial growth solution, confirming the controllability of the doping process. The absence of any impurities indicates a high purity of the synthesized samples. The data obtained confirm the possibility of precise control of the stoichiometry of zinc cobaltite. It is shown that the morphology of the grown samples depends on the stoichiometry of the precursors, providing controlled growth of nanostructured materials. It is shown that the hydrothermal method for the synthesis of ZnCo₂O₄ nanostructures allows obtaining materials with a wide range of stoichiometry from cobalt- to zinc-containing phases, which opens up opportunities for fine-tuning the effective, functional properties of ZnCo₂O₄.