Efficient Two-Dimensional Tin Halide Perovskite Light-Emitting Diodes via a Spacer Cation Substitution Strategy
Zhibin Wang, Fuzhi Wang, Biao Zhao, Songnan Qu, Tasawar Hayat, Ahmed Alsaedi, Laizhi Sui, Kaijun Yuan, Jianqi Zhang, Zhixiang Wei, Zhan’ao Tan
Abstract
Lead halide perovskites have attracted tremendous attention because of their impressive optoelectronic properties. However, the toxicity of lead remains a bottleneck for further commercial development. Two-dimensional Ruddlesden–Popper tin-based perovskites are lead-free and more stable compared to their three-dimensional counterparts, which have great potential in the optoelectronic device field. Herein, we demonstrate high-quality two-dimensional phenylethylammonium tin-iodide perovskite (PEA2SnI4) thin films by using toluene as the antisolvent. Furthermore, the PeLED performance is greatly improved by replacing the PEAI spacer cation with 2-thiopheneethyllamine iodide (TEAI). As a result, a TEA-based PeLED device is achieved with a low turn-on voltage of 2.3 V, a maximum luminance of 322 cd m–2, and maximum external quantum efficiency of 0.62%, which are the highest efficiency and brightness for pure red (emission peak = 638 nm) tin-based PeLEDs to date.