TiO2 nanorod arrays/ZnO nanosheets heterostructured photoanode for quantum-dot-sensitized solar cells

The three-dimensional heterostructured photoanode is considered to be an effective way to solve the problems of insufficient specific surface area and high electron recombination rate from one-dimensional nanomaterials. By combining the advantages of nanorods and nanosheets, we construct a novel TiO2 nanorod arrays/ZnO nanosheets (TNRAs/ZNSs) heterostructure as the photoanode in quantum-dot-sensitied solar cells (QDSSCs) by a controllable chemical bath deposition method at an appropriate temperature. The photoelectrochemical properties are measured by UV-Vis absorption spectra, current density-voltage (J-V), open-circuit voltage attenuation test (V-t) and electrochemical impedance spectroscopy (EIS). The results reveal that the TNRAs/ZNSs photoanode has larger specific surface area and slower electronic recombination rate, and its power conversion efficiency increases by 260% compared with TNRAs-based QDSSCs. This three-dimensional heterostructure exhibits distinct advantages and we believe that it can be used in other photoelectronic devices.