Recent progress of colloidal quantum dot based solar cells

Colloidal quantum dot (CQD) solar cells have attracted great interest due to their low cost and superior photo-electric properties. Remarkable improvements in cell performances of both quantum dot sensitized solar cells (QDSCs) and PbX (X=S, Se) based CQD solar cells have been achieved in recent years, and the power conversion efficiencies (PCEs) exceeding 12% were reported so far. In this review, we will focus on the recent progress in CQD solar cells. We firstly summarize the advance of CQD sensitizer materials and the strategies for enhancing carrier collection efficiency in QDSCs, including developing multi-component alloyed CQDs and core-shell structured CQDs, as well as various methods to suppress interfacial carrier recombination. Then, we discuss the device architecture development of PbX CQD based solar cells and surface/interface passivation methods to increase light absorption and carrier extraction efficiencies. Finally, a short summary, challenge, and perspective are given.