Plasma-assisted synthesis of p-Co3O4/n-ZnO Nanocomposites for Gas Sensors

The present contribution is focused on the design and characterization of p-Co3O4/n-ZnOnanocomposites as gas sensors for the detection of flammable/toxic analytes. A two-step PlasmaAssisted-Chemical Vapor Deposition (PA-CVD) process was used to develop the target systems. Thesynthetic approach consisted in the initial deposition of c-axis oriented ZnO on polycrystalline aluminasubstrates, followed by the over-dispersion of tailored Co3O4 amounts. A multi-technique analysis,involving Glancing Incidence X-ray Diffraction (GIXRD), Field Emission-Secondary ElectronMicroscopy (FE-SEM), and X-ray Photoelectron Spectroscopy (XPS), evidenced the successfuldeposition of Co3O4 particles on the ZnO matrix and the absence of Co-Zn-O ternary phases. Theobtained composite materials displayed attractive properties as gas sensors for acetone, ethanol andnitrogen dioxide.