Gan Zhixing, Xu Hao, Hao Yanling
Key Laboratory of Optoelectronic Technology of Jiangsu Province, School of Physical Science and Technology, Nanjing Normal University, Nanjing 210023, China.
Science for Life Laboratory, Department of Applied Physics, Royal Institute of Technology, SE-10691 Stockholm, Sweden.
Nanoscale. 2016 Apr 21;8(15):7794-807. doi: 10.1039/c6nr00605a.
Luminescent nanomaterials, with wide applications in biosensing, bioimaging, illumination and display techniques, have been consistently garnering enormous research attention. In particular, those with wavelength-controllable emissions could be highly beneficial. Carbon nanostructures, including graphene quantum dots (GQDs) and other graphene oxide derivates (GODs), with excitation-dependent photoluminescence (PL), which means their fluorescence color could be tuned simply by changing the excitation wavelength, have attracted lots of interest. However the intrinsic mechanism for the excitation-dependent PL is still obscure and fiercely debated presently. In this review, we attempt to summarize the latest efforts to explore the mechanism, including the quantum confinement effect, surface traps model, giant red-edge effect, edge states model and electronegativity of heteroatom model, as well as the newly developed synergistic model, to seek some clues to unravel the mechanism. Meanwhile the controversial difficulties for each model are further discussed. Besides this, the challenges and potential influences of the synthetic methodology and development of the materials are illustrated extensively to elicit more thought and constructive attempts toward their application.
发光纳米材料在生物传感、生物成像、照明和显示技术等领域有着广泛应用，一直以来都备受大量研究关注。特别是那些具有波长可控发射特性的材料可能会带来极大益处。碳纳米结构，包括石墨烯量子点（GQDs）和其他氧化石墨烯衍生物（GODs），具有依赖激发的光致发光（PL）特性，即它们的荧光颜色可以通过改变激发波长来简单调节，这引起了人们的广泛兴趣。然而，依赖激发的PL的内在机制目前仍不清楚，且存在激烈争论。在这篇综述中，我们试图总结探索该机制的最新研究成果，包括量子限域效应、表面陷阱模型、巨红边效应、边缘态模型和杂原子电负性模型，以及新发展的协同模型，以寻找一些线索来揭示该机制。同时，对每个模型存在争议的难点进行了进一步讨论。除此之外，还广泛阐述了合成方法和材料发展所面临的挑战及潜在影响，以引发更多关于其应用的思考和建设性尝试。
