Selective coordination of polyazin sapanisertib with halide vacancy for printable mesoscopic perovskite solar cells

The mitigation of under-coordinated Pb2+ (halide vacancy) defect remains an imperative challenge in the perovskite solar cells, especially printable mesoscopic perovskite solar cells (FP-PSCs). Here we report a commercial-available polyazin anticancer drug Sapanisertib as coordination passivator of halide vacancies in FP-PSCs, thereby achieving the photoelectric conversion efficiency (PCE) to 18.46%, along with a record certified PCE of 18.27%. In polazin Sapanisertib (Sap), there exists two kinds of nitrogen atoms: in-aromatic ring (in purine and oxazole rings, IAR-Ns) and out-aromatic ring (substituted amino groups, OAR-Ns). Through multiple characterizations, and DFT calculations show that substituted amino groups OAR-Ns hardly get interaction with the halide vacancy due to the distribution of charge density in Sapanisertib. Our work suggests that the selective coordination is of great significance for the design of high-performance passivators for printable mesoscopic perovskite solar cells. A commercial anticancer drug, Sapanisertib, has been discovered to be a selective passivator with nitrogen atoms within the aromatic ring for under-coordinated Pb2+ (halide vacancy) defects in printable mesoscopic perovskite solar cells (FP-PSCs). This discovery has resulted in a record certified photoelectric conversion efficiency (PCE) of 18.27% and an overall PCE of 18.46%. [Display omitted]