Enhanced performance of dye-sensitized solar cells based on TiO2/MnTiO3/MgTiO3 composite photoanode

• The composites film photoanodes were prepared by dip coating method.
• The MnTiO3 and MgTiO3 coating layer can effectively promote the dye adsorption.
• The MnTiO3/MgTiO3 layer could retard the charge recombination.
• The DSSC based on the TiO2/MnTiO3/MgTiO3 photoanode exhibited the highest conversion efficiency.

The TiO2/MnTiO3, TiO2/MgTiO3 and TiO2/MnTiO3/MgTiO3 composite photoanodes were prepared by immersing the TiO2 nanosheets film into the mixed solution of titanium tetrachloride and manganese chloride (or magnesium chloride), and followed by calcination treatment. The effects of MnTiO3 and MgTiO3 treatment on the photovoltaic performances of the dye-sensitized solar cells (DSSCs) were investigated. The MnTiO3 and MgTiO3 as coating layer on the surface of TiO2 can effectively promote the dye adsorption adhered to the photoanode film. The photoelectric conversion efficiency of the DSSC based on TiO2/MnTiO3 and TiO2/MgTiO3 photoanodes increased by 25.7% and 15.5% compared with that of pure TiO2-based DSSC, respectively. Furthermore, the DSSC based on the TiO2/MnTiO3/MgTiO3 photoanode exhibited the highest conversion efficiency of 6.39%, exceeding that of pure TiO2-based DSSC by a factor of 1.4. The highest efficiency observed for the DSSC based on this hybrid structure is attributed to the enhanced dye-absorption, fast electron transfer and the energy barrier formed by MnTiO3/MgTiO3 layer, which suppresses the charge recombination and increases the photocurrent. This investigation provides a new way for further improving the photoelectric conversion efficiency of the DSSCs.

The MnTiO3/MgTiO3 coating can effectively increase the dye adsorption and suppress the recombination of charges and reduce the dark current loss, and finally enhance the photoelectric conversion efficiency.Figure optionsDownload as PowerPoint slide