High-Performance Perovskite Photodetectors with Suppressed Dark Current Density via Small Molecule in Antisolvent Strategy.

Dark current density, a critical parameter in perovskite photodetectors (PPDs), largely depends on the quality of the perovskite film. Herein, we introduce a new small molecule in antisolvent strategy to enhance perovskite film quality during the crystallization of Cs(FAMA)Pb(IBr). COTIC-4Cl, an N-type narrow bandgap nonfullerene small molecule with specific functional group, could strongly bind to the uncoordinated Pb in the perovskite with assistance of antisolvent, enabling rapid supersaturation of perovskite solution and form dense structures under low-temperature annealing.

Imidazole-Based Ionic Liquid Engineering for Perovskite Solar Cells with High Efficiency and Excellent Stability.

Despite the remarkable progress of perovskite solar cells (PSCs), the substantial inherent defects within perovskites restrict the achievement of higher efficiency and better long-term stability. Herein, we introduced a novel multifunctional imidazole analogue, namely, 1-benzyl-3-methylimidazolium bromide (BzMIMBr), into perovskite precursors to reduce bulk defects and inhibit ion migration in inverted PSCs. The electron-rich environment of -N- in the BzMIMBr structure, which is attributed to the electron-rich adjacent benzene ring-conjugated structure, effectively passivates the uncoordinated Pb cations.