Enhanced performance of dye-sensitized solar cells based on meso/macroporous phosphotungstic acid/TiO2 photoanodes

A hierarchically meso/macroporous phosphotungstic acid/TiO2 (HPW/TiO2) composite has been synthesized and introduced into the photoanode of dye-sensitized solar cells (DSSCs). The performance of the cell with hierarchically HPW/TiO2 modified photoanode was enhanced compared to the pristine P25 cell. When the mass percentage of HPW/TiO2 is 15 wt% in the photoanode, an increase of 28.2% improvement in the conversion efficiency are obtained. The interfacial layer modified by HPW can retard the recombination of electrons and broad the absorption to the visible region; the introduction of hierarchically porous structure in the photoanode can increase light scattering and dye adsorption. All these merits are responsible for an efficient enhancement in energy conversion efficiency.