Synthesis, structure and ethanol sensing properties of Ga2O3-core/WO3-shell nanostructures

Ga2O3-core/WO3-shell nanostructures were synthesized by thermal evaporation of Ga2S3 powders followed by thermal evaporation of WO3 powders and their C2H5OH gas sensing properties were examined. Ga2O3-WO3 heterostructure formation turned out to enhance the C2H5OH gas sensing properties remarkably. Ga2O3-core/WO3-shell nanostructure sensors showed far stronger and faster response to C2H5OH gas than pristine Ga2O3 nanostructures sensors. The significant improvement in the response of the Ga2O3 nanostructures to C2H5OH gas by Ga2O3-WO3 heterostructure formation can be explained by a combination of the potential barrier-controlled carrier transport mechanism and the surface-depletion mechanism.