Solvent-Additive Engineering-Assisted Improvement of Interface Contact for Producing Highly Efficient Inverted Perovskite Solar Cells

摘要

Inverted perovskite solar cells (IPSCs) suffer from perishing interface contact dueto the non-wetting hole-transport layer (HTL). Herein, the several classes ofsolvent to the perovskite precursor (the process is defined as solvent-additiveengineering) for achieving an improvement in the interface contact betweennonwetting HTL and active perovskite layer, suitably achieving improved holeinterfacecharge transfer, are mixed. Also, a high-quality perovskite layer withhigh crystallinity, large grain distribution, and flat surface morphology is obtainedbased on solvent-additive engineering, which affords a lower bulk and interfacetrap density. IPSCs with the modified perovskite layer show suppression ofnonradiative recombination on the surface and in the bulk of the perovskite,thereby achieving an outstanding power conversion efficiency of 20.6%. Inaddition, IPSCs using a mixed-cation perovskite (FA_(0.83)Cs_(0.07)MA_(0.13)PbI_(2.64)Br_(0.39))are also fabricated and a highest efficiency of 22.1%, visualizing the broadapplicability of this method, is achieved. This simple, low-cost, and efficientsolvent-additive strategy can solve interface contact problems and improveperovskite quality, thus potentially giving rise to other applications.