Interfacing Pristine C₆₀ onto TiO₂ for Viable Flexibility in Perovskite Solar Cells by a Low‐Temperature All‐Solution Process

Abstract

A low‐temperature solution‐processed strategy is critical for cost‐effective manufacture of flexible perovskite solar cells (PSCs). Based on an aqueous‐processed TiO2 layer, and conventional fullerene derivatives replaced by a pristine fullerene interlayer of C60, herein a facile interface engineering for making all‐solution‐processed TiO2/C60 layers in flexible n‐i‐p PSCs is reported. Due to the improvement of the perovskite grain quality, promotion of interfacial charge transfer and suppression of interfacial charge recombination, the stabilized power conversion efficiency for the flexible PSCs reaches as high as 16% with high bending resistance retention (≈80% after 1500 cycles) and high light‐soaking retention (≈100% after 100 min). In addition, the stabilized efficiency is over 19% for the rigid TiO2/C60‐based PSCs. The present work with the facile low‐temperature solution process renders the practicability for high‐performance flexible PSCs applied to wearable devices, portable equipment, and electric vehicles.

Energy‐Level Modulation in Diboron‐Modified SnO2 for High‐Efficiency Perovskite Solar Cells

“…To clearly compare the electron extraction ability of SO and BSO film, we further performed the steady‐state photoluminescence (PL) and time‐resolved photoluminescence (TRPL) measurements (Figure g,h) based on the samples structure: ITO/SO/perovskite or ITO/BSO/perovskite. The PL intensity of BSO‐based perovskite is reduced significantly compared with SO‐based perovskite, ascribed to the more efficient extraction of photo‐generated electrons from the perovskite to the SnO 2 . In addition, the faster fluorescence decay (Table S1, Supporting Information) for the BSO‐based perovskite sample indicates that the B 2 Cat 2 treatment could further enhance the interfacial electron extraction.…”

Gradient Energy Band Driven High‐Performance Self‐Powered Perovskite/CdS Photodetector

“…Tremendous efforts are devoted to building self-powered perovskite photodetectors which do not require extra power supply. [14,15] To further enhance carrier transfer and suppress back recombination at the interface, the composite electron extraction layers, such as PCBM/C 60 , [16] TiO 2 /C 60 , [17] ZnO/ PCBM, [18] and TiO 2 /Al 2 O 3 /PCBM, [19] are developed, which www.advmat.de www.advancedsciencenews.com device exhibits large responsivity (0.48 A W −1 ), high detectivity (2.1 × 10 13 Jones), and fast response speed (0.54/2.21 ms) under 700 nm light illumination. In a photodiode, the photoexcited electron-hole pairs are separated by the inner electric fields at the electron extraction layer or hole extraction layer/perovskite interface, thus endowing the self-powered functionality.…”

“…[23] We reported graded CdS x Se 1-x nanobelt solar cells by utilizing continuous stepped energy levels to drive electrons and holes toward opposite direction. [14,15] To further enhance carrier transfer and suppress back recombination at the interface, the composite electron extraction layers, such as PCBM/C 60 , [16] TiO 2 /C 60 , [17] ZnO/ PCBM, [18] and TiO 2 /Al 2 O 3 /PCBM, [19] are developed, which Inspired by previous results, with the introduction of gradient built-in band bending at the charge extraction layer/perovskite interface, the energy band offset is expected to provide the driving force for enhanced carrier separation, suppressed electron reflux, and reduced recombination, boosting the performance of perovskite photodetectors.…”

Enhanced Efficiency and Stability of Planar Perovskite Solar Cells Using a Dual Electron Transport Layer of Gold Nanoparticles Embedded in Anatase TiO2 Films

“…Perovskite crystal growth can be controlled to tune the film morphology for regulating ion migration and the density of trap states, resulting in a reduction in carrier recombination and the charge transfer/extraction barrier. 10 − 12 In particular, a significant amount of effort has been focused on reducing ions transportation in the perovskite layers, 13 − 15 modifying the electron and hole selective layers, 16 − 18 as well as blocking the reactions between metal electrodes and halides. 19 …”