Efficient Charge Transfer in MAPbI 3 QDs/TiO 2 Heterojunctions for High-Performance Solar Cells.

Methylammonium lead iodide (MAPbI 3 ) perovskite quantum dots (QDs) have become one of the most promising materials for optoelectronics. Understanding the dynamics of the charge transfer from MAPbI 3 QDs to the charge transport layer (CTL) is critical for improving the performance of MAPbI 3 QD photoelectronic devices. However, there is currently less consensus on this. In this study, we used an ultrafast transient absorption (TA) technique to investigate the dynamics of charge transfer from MAPbI 3 QDs to CTL titanium dioxide (TiO 2 ), elucidating the dependence of these kinetics on QD size with an injection rate from 1.6 × 10 10 to 4.3 × 10 10 s -1 . A QD solar cell based on MAPbI 3 /TiO 2 junctions with a high-power conversion efficiency (PCE) of 11.03% was fabricated, indicating its great potential for application in high-performance solar cells.