All‐inorganic CsPbI3 holds promise for efficient tandem solar cells, but reported fabrication techniques are not transferrable to scalable manufacturing methods. Herein, printable CsPbI3 solar cells are reported, in which the charge transporting layers and photoactive layer are deposited by fast blade‐coating at a low temperature (≤100 °C) in ambient conditions. High‐quality CsPbI3 films are grown via introducing a low concentration of the multifunctional molecular additive Zn(C6F5)2, which reconciles the conflict between air‐flow‐assisted fast drying and low‐quality film including energy misalignment and trap formation. Material analysis reveals a preferential accumulation of the additive close to the perovskite/SnO2 interface and strong chemisorption on the perovskite surface, which leads to the formation of energy gradients and suppressed trap formation within the perovskite film, as well as a 150 meV improvement of the energetic alignment at the perovskite/SnO2 interface. The combined benefits translate into significant enhancement of the power conversion efficiency to 19% for printable solar cells. The devices without encapsulation degrade only by ≈2% after 700 h in air conditions.
All-inorganic halide perovskites hold promise for emerging thin-film photovoltaics due to their excellent thermal stability. Unfortunately, it has been challenging to achieve high-quality thin films over large areas using scalable methods under realistic ambient conditions. Here, we provide important lessons on controlling the solidification and crystallization of CsPbI2Br perovskite inks during ambient scalable fabrication, with results of superior thin-film quality and device performance compared to lab-scale processes.
Perovskite solar cells exhibit not only high efficiency under full AM1.5 sunlight, but also have great potential for applications in low‐light environments, such as indoors, cloudy conditions, early morning, late evening, etc. Unfortunately, their performance still suffers from severe trap‐induced nonradiative recombination, particularly under low‐light conditions. Here, a holistic passivation strategy is developed to reduce traps both on the surface and in the bulk of micrometer‐thick perovskite film, leading to a record efficiency of 40.1% under 301.6 µW cm−2 warm light‐emitting diode (LED) light for low‐light solar‐cell applications. The involvement of guanidinium into the perovskite bulk film and 2‐(4‐methoxyphenyl)ethylamine hydrobromide (CH3O‐PEABr) passivation on the perovskite surface synergistically suppresses the trap states. The charge carrier lifetimes of the perovskite film increase by tenfold and fivefold to 981 ns and 8.02 µs at the crystal surface and in its bulk, respectively. The decreased nonradiative recombination loss translates to a high open‐circuit voltage (Voc) of 1.00 V, a high short‐circuit current (Jsc) of 152.10 µA cm−2, and a fill factor (FF) of 79.52%. Note that this performance also stands as the highest among all photovoltaics measured under indoor light illumination. This work of trap passivation for micrometer‐thick perovskite film paves a way for high‐performance, self‐powered IoT devices.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.