All‐Inorganic Hetero‐Structured Cesium Tin Halide Perovskite Light‐Emitting Diodes With Current Density Over 900 A cm⁻² and Its Amplified Spontaneous Emission Behaviors

Abstract

Pursuing novel new materials for fabricating efficient electrically pumped lasers is the emphasis of researchers for decades. Although organic semiconductors with high gain have been reported previously, a significant challenge remains in using them for electrically pumped lasers due to their low carrier mobility. Recently, hybrid halide perovskites have been reported to possess high carrier mobility and optical gain which allows them to be used for various optoelectronic applications. To explore the feasibility of using them as possible candidates for electrically pumped lasers, tin (Sn)‐based perovskite light‐emitting diodes (PeLEDs) with all‐inorganic heterostructure are fabricated by the vapor‐deposition process. The all‐inorganic hetero‐structured PeLEDs exhibited a maximum EQE of ≈0.34%, and withstood current density up to 915 A cm−2 with small emission zone of 0.01 mm2. In addition, by vacuum vapor deposition, extremely smooth and uniform cesium tin halide perovskite films with small grain size (≈60 nm) are obtained, in which low threshold (≈7 µJ cm−2) of their amplified spontaneous emission was presented. These characteristics demonstrate the great potential of using them as gain media for electrically pumped lasers.

Perovskites for Next-Generation Optical Sources

“…All-inorganic CsSnX3 perovskites have been reported and applied to LEDs 67 . Thin SnX2 and CsX films were sequentially deposited by vapor deposition then annealed to form uniform CsSnX3 films via interdiffusion.…”

High‐Quality Cs2AgBiBr6 Double Perovskite Film for Lead‐Free Inverted Planar Heterojunction Solar Cells with 2.2 % Efficiency

“…[1][2][3] Light emitting iodide device based on perovskite material have also made exciting progress. [4][5][6][7] To promote the large-scale commercialization of this promising optoelectronic photovoltaic device, the long-term stability and toxicity of the Pb-based perovskite material remain the biggest challenges. [8][9][10] As a consequence, many researches have turned their attention to the exploration of Pb-free perovskite material with high ambient stability and low toxicity.…”

Metal Halide Perovskite Light‐Emitting Devices: Promising Technology for Next‐Generation Displays

“…Films prepared by toluene dripping had compact grains with fewer pinholes and cracks at the grain boundaries, and the infrared PeLEDs fabricated from them exhibited better device performance, with an EQE of 3.8%, a radiance of 40 W sr −1 m −2 , and EL peak at 950 nm. CsSnBr 3 ‐based all‐inorganic PeLEDs with EL peak at 672 nm and a maximum EQE of 0.34% were fabricated via the vapor‐deposition process by Yuan et al To date, the highest luminance of 350 cd m −2 was achieved for the lead‐free PeLEDs by using 2D (C 18 H 35 NH 3 ) 2 SnBr 4 layered perovskites as orange emitters …”