S₈ Additive Enables CsPbI₂Br Perovskite with Reduced Defects and Improved Hydrophobicity for Inverted Solar Cells

Abstract

Though prized for excellent thermal stability, inorganic perovskites are still behind organic/inorganic hybrid perovskites due to their high‐density defects and poor hydrophobicity. Herein, trace hydrophobic S8 is used as additive to optimize the solution‐processed CsPbI2Br perovskite film. A series of characterizations reveal that S8 additive not only leads to retarded crystallization of α‐CsPbI2Br perovskite at low temperature (<150 °C) via self‐formed Pb(S8)x2+ intermediate but also induces efficient grain‐boundary passivation via distinctive PbS coordination interaction and reduced wettability on perovskite surface, which all point to the formation of the perovskite film with reduced defects and improved hydrophobicity. As a result, the inverted perovskite solar cells (PSCs) based on the optimized all‐inorganic perovskite of CsPbI2Br:S8 deliver an increased power conversion efficiency (PCE) from 12.76% to 14.46% as well as remarkably enhanced device stability under thermal or ambient condition. This work thus provides a simple way as well as new insights for boosting the performance of solution‐processed all‐inorganic perovskite.

Thiophene Derivatives as Ligands for Highly Luminescent and Stable Manganese-Doped CsPbCl3 Nanocrystals

“…The peaks shift to 143.00 eV and 138.10 eV after the addition of TBA, where both peaks slightly shift approximately 0.15 eV toward the higher binding energy region. According to previous reports (Liu L. et al, 2018;Noel et al, 2020;Choi et al, 2021;He et al, 2021;Ren et al, 2021;Yuan et al, 2021), the upward shift of Pb 4f peaks might come from S atoms of the thiophene in TBA additives partially occupying halide vacancies and forming Pb-S bonds with Pb ions in the perovskite crystals (Noel et al, 2020). Meanwhile, it is noteworthy that the Cs 3d and Cl 2p spectra display negligible shifts upon TBA incorporation (Supplementary Figure S5).…”

Interfacial Engineering by In Situ Building of a 3D/2D Heterojunction for Inverted CsPbI2Br Solar Cells: Beyond Moisture Proof

“…The device with BIZI also achieved a stabilized PCE of 12.38% at the maximum power output point, higher than that (8.01%) of the pristine device (Figure g). Nevertheless, the hysteresis is not remarkably reduced upon the BIZI posttreatment (see Figure S14 and Table S1), which might account for the discrepancy between the stabilized PCE and the maximum PCE derived from the J–V curve (with reverse scan). − …”

Water-stable and hydrophobicity tunable organolead halide materials with Pb–N coordination for electrochemical CO2 reduction

“…[30][31][32] The hydrophobicity can effectively prevent the penetration of moisture and strengthen the water stability. [33][34][35][36][37] To conrm this, inltration processes of the water molecule into 4,4BpyPbCl 2 and 4,4BpyPbI 2 were explored, as shown in Fig. S10.…”