Li Yuhao, Xu Junhao, Hu Tengbo, Shi Guangli, Peng Yao, Qiao Feng, Zhang Lietao, Zhao Chuanyu, Kuang Ye, Shen Longhai
College of Science, Shenyang Ligong University, Shenyang 110159, P. R. China.
Zolix Instruments Co., Ltd., Beijing 101102, P. R. China.
Inorg Chem. 2024 Sep 16;63(37):17032-17042. doi: 10.1021/acs.inorgchem.4c02701. Epub 2024 Sep 2.
Rare earth (RE) dopants can modulate the bandgap of oxides of indium and gallium and provide extra upconversion luminescence (UCL) abilities. However, relevant UCL fine-tuning strategies and energy mechanisms have been less studied. In this research, InGaO, Ho monodoped and Yb/Ho codoped InO, and Ho monodoped YbGaO nanoparticles (NPs) were synthesized by a solvothermal method. The effects of Yb and Ho dopants on the crystal structures, UCL properties, and optical bandgaps of the oxides were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), UCL spectroscopy, and measurements of decay times, pump power dependence, and transmittance spectra. The crystal structures of oxide products of indium and gallium were significantly modified with RE dopants. InO and YbGaO were selected as the host materials. For Yb/Ho codoped InO NPs, there existed energy transfers from the defect states of InO to Ho and from Yb to Ho. With a fixed Ho concentration, InO:0%Yb,2%Ho NPs showed the optimal UCL properties mainly due to InO-Ho energy transfer and Ho-Yb energy-back-transfer, while with a fixed Yb concentration, InO:5%Yb,3%Ho NPs with a slight YbO impurity and YbGaO:2%Ho NPs did mainly due to Ho-Ho cross-relaxation. Besides, the optical bandgaps of InO and YbGaO were noticeably broadened with RE dopants. These findings can offer feasible directions for the synthesis and UCL fine-tuning of RE-doped oxides of indium and gallium and improve their multifunction application prospects in the fields of semiconductor and UCL nanomaterials.
稀土（RE）掺杂剂可以调节铟和镓的氧化物的带隙，并提供额外的上转换发光（UCL）能力。然而，相关的UCL微调策略和能量机制的研究较少。在本研究中，通过溶剂热法合成了InGaO、Ho单掺杂和Yb/Ho共掺杂的InO以及Ho单掺杂的YbGaO纳米颗粒（NPs）。通过X射线衍射（XRD）、透射电子显微镜（TEM）、UCL光谱以及衰减时间、泵浦功率依赖性和透射光谱测量，表征了Yb和Ho掺杂剂对氧化物的晶体结构、UCL特性和光学带隙的影响。铟和镓的氧化物产物的晶体结构被RE掺杂剂显著改变。选择InO和YbGaO作为主体材料。对于Yb/Ho共掺杂的InO NPs，存在从InO的缺陷态到Ho以及从Yb到Ho的能量转移。在Ho浓度固定的情况下，InO:0%Yb,2%Ho NPs表现出最佳的UCL特性，主要归因于InO-Ho能量转移和Ho-Yb能量反向转移；而在Yb浓度固定的情况下，具有轻微YbO杂质的InO:5%Yb,3%Ho NPs和YbGaO:2%Ho NPs主要归因于Ho-Ho交叉弛豫。此外，RE掺杂剂使InO和YbGaO的光学带隙明显变宽。这些发现可以为铟和镓的RE掺杂氧化物的合成和UCL微调提供可行的方向，并改善它们在半导体和UCL纳米材料领域中的多功能应用前景。
