Department of Chemistry and ‡Department of Materials Science and Engineering, Texas A&M University , College Station, Texas 77843, United States.
Nano Lett. 2016 Dec 14;16(12):7376-7380. doi: 10.1021/acs.nanolett.6b02772. Epub 2016 Nov 2.
We report the one-pot synthesis of colloidal Mn-doped cesium lead halide (CsPbX) perovskite nanocrystals and efficient intraparticle energy transfer between the exciton and dopant ions resulting in intense sensitized Mn luminescence. Mn-doped CsPbCl and CsPb(Cl/Br) nanocrystals maintained the same lattice structure and crystallinity as their undoped counterparts with nearly identical lattice parameters at ∼0.2% doping concentrations and no signature of phase separation. The strong sensitized luminescence from d-d transition of Mn ions upon band-edge excitation of the CsPbX host is indicative of sufficiently strong exchange coupling between the charge carriers of the host and dopant d electrons mediating the energy transfer, essential for obtaining unique properties of magnetically doped quantum dots. Highly homogeneous spectral characteristics of Mn luminescence from an ensemble of Mn-doped CsPbX nanocrystals and well-defined electron paramagnetic resonance spectra of Mn in host CsPbX nanocrystal lattices suggest relatively uniform doping sites, likely from substitutional doping at Pb. These observations indicate that CsPbX nanocrystals, possessing many superior optical and electronic characteristics, can be utilized as a new platform for magnetically doped quantum dots expanding the range of optical, electronic, and magnetic functionality.
我们报告了一种将胶体 Mn 掺杂的铯铅卤（CsPbX）钙钛矿纳米晶体一锅法合成的方法，以及激子和掺杂离子之间有效的粒子内能量转移，从而导致强烈的敏化 Mn 发光。Mn 掺杂的 CsPbCl 和 CsPb（Cl/Br）纳米晶体与未掺杂的纳米晶体具有相同的晶格结构和结晶度，在约 0.2%的掺杂浓度下，晶格参数几乎相同，没有相分离的迹象。在 CsPbX 主体的能带边缘激发下，Mn 离子的 d-d 跃迁产生的强烈敏化发光表明，载流子和掺杂 d 电子之间的电荷转移具有足够强的交换耦合，这对于获得磁性掺杂量子点的独特性质是必不可少的。从一组 Mn 掺杂的 CsPbX 纳米晶体中获得的 Mn 发光的高度均匀的光谱特性和 Mn 在宿主 CsPbX 纳米晶体晶格中的明确电子顺磁共振光谱表明，存在相对均匀的掺杂位置，可能来自 Pb 的取代掺杂。这些观察结果表明，具有许多优越的光学和电子特性的 CsPbX 纳米晶体可以用作磁性掺杂量子点的新平台，扩展了光学、电子和磁性功能的范围。
