Formation of novel homojunction device using p-type ZnO:Co shell coating on n-type ZnO nanowires

P-type ZnO:Co thin film was spin coated onto n-type ZnO nanowire arrays to form a novel ZnO homojunction device using a fully solution-based process. The optoelectronic and structural properties of the homojunction device were extensively characterized by using scanning electron microscopy, X-ray diffraction, energy dispersive spectroscopy and photoluminescence emission measurement and current voltage measurement. It was found that the applied ZnO:Co coating bundles the nanowires together and suppress surface defects on the nanowire. Dark and illuminated device confirms the pn junction formation and its light sensitivity properties.