CdS QD-CQD co-sensitized TiO2 solar cells: preparation and photoelectrochemical properties

CdS quantum dot and ZnS quantum dot as passivation layers were deposited on the surface of TiO2/C-TiO2/TiO2 multilevel structure photoanode. And solar cells were assembled by using the photoanode. The photoanodes were characterized by X-ray diffraction, transmission electron microscope, fourier transform infrared and ultraviolet-visible adsorption spectra. Photoelectrochemical properties of devices were tested by electrochemical workstation. The results show that the optimum conditions for the photoelectric performance of the device are cadmium acetate as the cadmium source and sensitization 9 times, and the TiO2 film layer is 3 layers. Under such process conditions, the short-circuit current density (J(sc)) is 2.28 mA/cm(2), open-circuit voltage (V-oc) is 0.30 V, fill factor (FF) is 0.45, and photoelectric conversion efficiency (eta) is 0.14%. After introducing carbon quantum dots, the filling factor is increased by 100% to 0.40, and the all-optical conversion efficiency is improved by 28%, to 0.18%.