High-entropy hybrid perovskites with disordered organic moieties for perovskite solar cells

Abstract

High-entropy materials consisting of disordered multiple components can exhibit enhanced materials properties compared with their individual constituents. Although various high-entropy materials have been developed based on the configurational disorder of mixed inorganic components, the potential of organic moieties for high-entropy structures remains underexplored. Here we report a family of high-entropy organic–inorganic hybrid perovskites for photovoltaic applications. By mixing different A-site organic cations with various alkyl chains, we obtain a hybrid crystal structure with ordered inorganic frameworks and disordered organic moieties, leading to increased entropy. The hybrid perovskite exhibits superior properties compared with its single-component counterpart, including increased resilience to structural transitions and heat stress. When used in solar cells, the high-entropy hybrid perovskite leads to devices with a power conversion efficiency of 25.7% (certified, 25.5%) for an inverted-cell architecture. Cells retain over 98% of their initial power conversion efficiency after 1,000 h of operation under continuous illumination (AM 1.5 G), with a linear extrapolation to the T90 value of 5,040 h. In particular, the structural disorder of this class of high-entropy materials can also reduce non-radiative recombinations for a wide range of perovskite composition, stoichiometry deviation, film-processing history and device architecture. This universal and error-tolerant strategy can, thus, benefit the production yield of perovskite solar cells in future industrial mass production. Given the rich chemistry of organic moieties and mixing configuration, this work may also open up more opportunities to tune the stability and optoelectronic properties of perovskite materials for photoelectric applications. High-entropy hybrid perovskites exhibit improved materials properties compared with their individual components. When employed in solar cells, champion devices achieve a certified power conversion efficiency of 25.5% and an extrapolated T90 lifetime of over 5,000 h under continuous light soaking.