Gas Sensitivity of the Surface Potential of Hybrid Porphyrin-ZnO Nanorods

AbstractIn this paper we study the sensitivity to volatile organic vapors of the surface potential of metalloporphyrins coated ZnO nanorods. The hybrid material has been growth with an original method based on the direct addition of metalloporphyrins to the hydrothermal precursor solution. The resulting film shows a complete coating of the ZnO surface expected to improve the photovoltaic characteristics. The chemical sensitivity of the surface potential has been measured in dark and in white light illumination. For sake of comparison, the hybrid material has been compared with those obtained from a casting coated porphyrin functionalized ZnO nanorods. Results show that the material preparation strongly influences the sensor properties, and in case of the hybrid material the illumination with visible light elicits an increase of the sensor response that is proportional to the ability of the volatile compound to donate electrons