All-solution preparation of perovskite light-emitting diodes in ambient air through film-forming regulation of light-emitting layers based on dual-additive doping and oxygen plasma treatment

Organic-inorganic hybrid perovskites are promising for optoelectronics owing to their high color purity, tunable bandgaps, and low nonradiative recombination rates. However, challenges such as rough surfaces and poor film-forming properties constrain the optoelectronic performance of light-emitting devices. Herein, the PEDOT:PSS film treated by oxygen plasma serves as the hole transport layer, while the formation of perovskite films is optimized by dual-additive doping of PEO and TPBi in ambient air. The results show that the PEDOT:PSS films with PSSH-rich after oxygen plasma treatment provide more nucleation sites, favoring the formation of the perovskite film. Meanwhile, the dual-additive prompts to form a dense and uniform film as well. The intrinsic mechanisms involve PEO as a binder to fill grain gaps and improve water-oxygen stability in the perovskite film, while TPBi acts as a passivator to stimulate uniform nucleation and dense crystallization, improving the grain coverage of the light-emitting layer. Under atmospheric conditions, all-solution processed perovskite devices reach a maximum luminance of 810.4 cd m −2 and a maximum current efficiency of 0.437 cd A −1 . This work highlights the significance of using oxygen plasma treatment and additives to improve the performance of perovskite films and achieve superior PeLEDs.