Improvement of dye-sensitized solar cells: what we know and what we need to know

The dye-sensitized solar cell (DSC) has been regarded as one of the most promising next-generation solar cells. Tremendous research efforts have been invested to improve the efficiency of solar energy conversion which is generally determined by the light harvesting efficiency, electron injection efficiency and undesirable charge recombination degree. Recently, charge recombination and electron injection efficiency, that are correlated with the open circuit voltage (Voc), have received more and more attention for their crucial roles in the further improvement of the efficiency of DSCs. In this review article, the factors that affect charge recombination and electron injection efficiency systematically discussed in order to formulate basic guidelines and strategies for improving Voc and the overall performance of DSCs is reviewed.