Surface analysis of Ga-doped 3D urchin-like ZnO structure and density functional theory investigation of the quenching in photoluminescence property
Surface analysis of Ga-doped 3D urchin-like ZnO structure and density functional theory investigation of the quenching in photoluminescence property
复制标题
DOI：
10.1016/j.jallcom.2014.03.114
复制
发表时间：
2014-08
影响因子：
6.2
通讯作者：
Ling-min Yu;Xin-hui Fan;M. Lei;Jiansong Wei;Y. Jin;Wen Yan
中科院分区：
文献类型：
--
作者：
Ling-min Yu;Xin-hui Fan;M. Lei;Jiansong Wei;Y. Jin;Wen Yan
以不同摩尔比的氧化镓为掺杂源，采用热蒸发法制备了不同形貌的掺镓三维海胆状氧化锌结构。用场发射扫描电子显微镜、X射线衍射仪、高分辨透射电子显微镜和X射线光电子能谱(XPS)分析了薄膜的形貌、微观结构和化学状态。研究证实，随着掺杂量的增加，三维海胆状氧化锌结构的形貌发生了明显的变化。X射线光电子能谱分析表明，Ga已掺入到氧化锌晶格中。光致发光发射峰在5%Ga2O_3掺杂下发生了明显的猝灭。通过密度泛函理论计算，讨论了发射猝灭的原因。结果表明，O-2p态与Zn-3d和Ga-4S、Ga-4P略有杂化，导致导带向下，引入相关杂质能级，导致非辐射跃迁增加。
Ga-doped 3D urchin-like ZnO structures with different morphologies have been synthesized by thermal evaporation with different molar ratio gallium oxide as the dopant source. The morphology, microstructure and chemical state were determined by field emission scanning electron microscopy, X-ray diffraction, high-resolution transmission electron microscopy, and X-ray photoelectron spectroscopy (XPS). The investigation confirmed that the morphologies of the 3D urchin-like ZnO structure had a significant transform with the increase of the dopant. The XPS result indicates that Ga is incorporated into the ZnO lattice. photoluminescence emission peak has been found to be quenched remarkably caused by 5 mol% Ga2O3dopant. The reason of the emission quench is discussed by means of density functional theory calculations. It is found that O-2p states slightly hybridize with Zn-3d and Ga-4s, Ga-4p states giving rise to the conduction band downward and introduction of the correlative impurity levels, which will result in the increase of non-radiative transition.