Tin Oxide/Amphiphilic Polymer Double-Layered Hole Transporter for High-Efficiency Tin Perovskite Solar Modules

An exquisite, engineering of two poor hole transporting materials (HTMs, SnO, and PDTON) to form an excellent double-layered HTL (SnO/PDTON) for inverted tin-perovskite solar modules (TPSMs) is developed. SnO/PDTON has better photovoltaic performance than the commonly used PEDOT:PSS HTM when large-area TPSMs are fabricated. Thermally evaporated SnO (that is a simple, available oxide with high hole mobility, good transparency, and adjustable frontier orbitals energy levels) film is used as a main hole transporting layer (HTL). Amphiphilic polymer PDTON (having the amine and ether groups on the side chains) film is used as a Co-HTL, cross-linker, passivator, and interface modification agent, as unveiled various physicochemical studies. Double-layered SnO/PDTON with a flat morphology and good affinity toward perovskite precursor solution creates also a proper surface for depositing large-area, high-quality TPsk film. Therefore, TPSM (25.2 cm² active area on 10 cm × 10 cm ITO substrate) based on double-layered SnO/PDTON HTL achieving an efficiency over 10% with a negligible current hysteresis is reported for the first time. This study emphasizes not only the exquisite design of combining the specific characteristics of two prosaic HTMs to become a good double-layered HTL but also gives a direction toward fabricating TPSMs to be applied in all-perovskite tandem solar module.