Herein, a series of Pb_1-xNb_xSe QDs were prepared via 4,4-bis(carbazole-9-yl)biphenyl assisted microwave approach for NIR-QLED applications. The structural phases and crystalline dimension were accentuated by XRD. The diffraction patterns showed a cubic phase at all Nb-contents. The TEM measurements scrutinized the increase of the particle size from 2.4 ± 0.2 nm to 9.9 ± 0.3 nm with increasing the Nb-amounts. The high resolution transmission electron microscopy (HRTEM) measurements inspected that the d-spacing increases with the increase of the Nb-atoms concentration and the prepared nanocrystals tend to grow along the (111) direction. The energy-dispersive X-ray spectroscopy (EDS) and the X-ray photoelectron spectroscopy (XPS) measurements revealed the stoichiometry of the prepared nanocrystals and the oxidation states of the Nb, Pb, and Se ions are 2+, respectively. The optical absorbance spectroscopy measurement of Pb_1-xNb_xSe QDs revealed the ability of Nb-atoms to modify the bandgaps of PbSe QDs from 1.62 eV to 1.28 eV. The luminescence intensity is increased by 10 folds and the spectral bandwidth is decreased due to the doping of PbSe QDs with Nb-atoms. The doping of PbSe QDs with Nb-atoms increases the quantum yield to 75% and decreases the Stokes shift by 9 folds. These unique characteristics may enable the Pb_1-xNb_xSe QDs to be employed for the manufacture of highly luminescent NIR-QLED devices.

这里，一系列 Pb _1-x Nb _xSe QDs 是通过 4,4-双（咔唑-9-基）联苯辅助微波方法制备的，用于 NIR-QLED 应用。XRD 增强了结构相和晶体尺寸。衍射图在所有 Nb 含量下均显示立方相。TEM 测量仔细观察了随着 Nb 含量的增加，粒径从 2.4 ± 0.2 nm 增加到 9.9 ± 0.3 nm。高分辨率透射电子显微镜 (HRTEM) 测量发现 d 间距随着 Nb 原子浓度的增加而增加，并且制备的纳米晶体倾向于沿 (111) 方向生长。能量色散 X 射线光谱 (EDS) 和 X 射线光电子能谱 (XPS) 测量揭示了制备的纳米晶体的化学计量和 Nb、Pb 和 Se 离子的氧化态分别为 2+。_1-x Nb _x Se QD 揭示了 Nb 原子将 PbSe QD 的带隙从 1.62 eV 修改为 1.28 eV 的能力。由于用 Nb 原子掺杂 PbSe QD，发光强度增加了 10 倍，光谱带宽降低。用 Nb 原子掺杂 PbSe QD 将量子产率提高到 75%，并将斯托克斯位移降低 9 倍。这些独特的特性可以使 Pb _1-x Nb _x Se QD 能够用于制造高亮度 NIR-QLED 器件。