Nonionic surfactant assisted in-situ growth of all-inorganic perovskite film for bright pure red light-emitting devices

Abstract

Smooth and uniform morphology with low trap defects is important for the development of efficient perovskite light-emitting devices (PeLEDs). Pure red PeLEDs based on a facile one-step solution method still suffer moderate electroluminescent performance due to poor controllability for film growth. Here, we take advantage of coordination effects from surfactant additives to control the perovskite crystallization and suppress the nonradiative recombination. It is found that the introduction of Tween-80 (T80) in the precursor could not only improve the surface morphology with decreased roughness (RMS of 1.43 nm) but also enhance the radiative efficiency. As a result, efficient pure-red perovskite light-emitting devices were obtained with a brightness of 891 cd/m2, a current efficiency of 2.42 cd/A, and an EQE of 4.17 %. Our results would shed light on the film morphology control through additive engineering towards high-performance PeLEDs.