激光烧蚀制备石墨烯量子点的多发光带的荧光光谱研究

Exploration of Multi-Frequency Photoluminescence Spectrum of Graphene Quantum Dots(GQDs)Produced by Pulsed Laser Ablation

石墨烯量子点作为二维范德瓦尔斯晶体量子点的典型代表,具有一系列的优异性质和光明的应用前景[1]。特别是石墨烯量子点优异的发光特性,使其在细胞成像、荧光传感等领域表现出巨大的应用潜力[2-3]。然而,对石墨烯量子点发光机制的研究尚不清晰,这大大限制了石墨烯量子点发光的应用。其中一个重要原因在于,发光机制的实验和理论研究需要纯净的石墨烯量子点样品,以突显石墨烯量子点本身的发光。但常用的化学制备方式,由于需要浓酸、强碱、强氧化剂、高温或高压等条件,使得制备的石墨烯量子点常含有杂质。而杂质的存在会使发光机制研究中涉及到的因素变得复杂,部分杂质会使量子点发光减弱甚至淬灭。虽然传统的制备石墨烯量子点的方式都适合其相应的应用目标,但作为研究石墨烯量子点发光机制的目标还远远不够,因此就需要寻找制备高纯度的量子点的方法,特别是物理制备方法,以避免化学反应,并研究石墨烯量子点的荧光光谱。

Graphene quantum dots(GQDs)as a typical representative of two-dimensional van der Waals crystal quantum dots,with a series of excellent properties and bright application prospects.However,the research on the luminescence mechanism of graphene GQDS is not clear,which greatly limits the application of GQDs luminescence.One of the important reasons is that the presence of impurities will complicate the factors involved in the study of luminescence mechanism,and some impurities will weaken or even quench the luminescence of GQDs.In this paper,high purity graphene quantum dots were prepared by laser ablation and their multi-frequency optical properties were studied.