Two-dimensional (2D) perovskites have become a research hotspot due to their large exciton binding energy and excellent stability. However, it is difficult to achieve longer wavelength emission than blue and green light in the 2D perovskites owing to their wide band gap resulting from their strong quantum confinement. Herein, we demonstrate a simple, efficient and low energy consumption crystallization method at room temperature to synthesize Mn²⁺ ion doped 2D (PEA)₂PbBr₄ nanocrystals (NCs) with dual-color emission centered at 410 nm from the exciton transition of the host and 600 nm from the d–d transition of Mn²⁺ ions. The periodic XRD peaks prove the formation of 2D perovskites. It is reassuring that the high PLQY of 54% has been achieved in the Mn²⁺ ion doped 2D (PEA)₂PbBr₄ NCs. The temperature-dependent and time-resolved spectra illustrate the efficient energy transfer from excitons to Mn²⁺ dopant ions. The realization of white LEDs with different color temperatures presents an opportunity and prospect for Mn²⁺ ion doped 2D perovskites in LED application.

中文翻译：

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钙锰矿型双色发射Mn2 +离子掺杂（PEA）2PbBr4钙钛矿型发光二极管

二维（2D）钙钛矿因其大的激子结合能和出色的稳定性而成为研究热点。但是，由于2D钙钛矿中的蓝光和绿光由于强的量子限制而产生的宽带隙，因此很难实现比蓝光和绿光更长的波长发射。在这里，我们演示了一种简单，高效且低能耗的室温结晶方法，该方法可合成双色发射中心为410 nm的Mn ²⁺离子掺杂的2D（PEA）₂ PbBr ₄纳米晶体（NCs），从其激子跃迁开始。主体和Mn ²⁺的d–d跃迁600 nm离子。周期性的XRD峰证明了2D钙钛矿的形成。令人放心的是，在Mn ²⁺离子掺杂的2D（PEA）₂ PbBr ₄ NC中实现了54％的高PLQY 。温度依赖性和时间分辨光谱说明了从激子到Mn ²⁺掺杂离子的有效能量转移。具有不同色温的白色LED的实现为Mn ²⁺离子掺杂的2D钙钛矿在LED应用中提供了机会和前景。