煤基石墨烯量子点的制备与理化性质研究进展

Research progress on preparation and physicochemical properties of coal-based graphene quantum dots

石墨烯量子点(GQDs)显著的量子限域效应和边缘效应已经引起人们极大的研究兴趣。它不仅展现出稳定的光致发光现象,而且具有良好的溶解性和化学惰性等诸多优点,使其广泛应用于生物成像、光催化剂和传感器等领域。受限于传统制备方法原料昂贵和操作繁琐等原因,GQDs的工业发展受到严重阻碍。煤及其衍生物不仅具有价格低廉和储量丰富等优点,而且其内部固有的无序结构和小晶域显示出比石墨、石墨烯、氧化石墨烯和富勒烯等碳材料制备GQDs更大的优势,可以简单地通过物理、化学或电化学方法剥离煤及其衍生物内部的芳香环簇来制备GQDs。本文首先总结了煤基石墨烯量子点(C-GQDs)的“自上而下”合成方法及其优缺点。然后对C-GQDs的结构形态、化学成分、荧光性质及其影响因素进行分析。进而阐述C-GQDs在传感器、生物成像和能源领域等的应用进展。最后从制备方法、碳源选择和研究方向等方面对C-GQDs的未来发展进行探讨,提出以下几点试验方案:①H_(2)O_(2)为氧化剂,热变煤为碳源的试验;②超高有机硫煤为碳源,除硫酸和硝酸氧化法外的其他试验;③煤显微组分为碳源的试验。此外,通过试验得出的基础数据和计算机模拟技术相结合,解决当前研究存在的荧光颜色单一和量子产率较低等问题。从而达到煤炭资源清洁利用和GQDs绿色发展的目的。

Graphene quantum dots(GQDs)have attracted great research interest due to their remarkable quantum confinement and edge effects.In addition to exhibiting stable photoluminescence,it also has many advantages such as low cytotoxicity,good solubility and chemical inertness,making it widely used in bioimaging,photocatalysts and sensors.The industrial development of GQDs has been seriously hampered by the expensive raw materials and tedious operation of traditional preparation methods.Coal and its derivatives not only possess the characteristics of low price and abundant reserves,but also show greater advantages than graphite,graphene,graphite oxide and other carbon materials in the preparation of GQDs due to its inherent internal disorder structure and small crystal domain.GQDs can be prepared by simply stripping the aromatic ring clusters inside the coal and its derivatives through physical,chemical or electrochemical methods.This review first summarizes the“top-down”synthesis method of coal-based graphene quantum dots(C-GQDs)and its pros and cons.Then the structural morphology,chemical composition,fluorescence properties of C-GQDs and their influencing factors are ana lyzed.Further,we describe the progress in applications of C-GQDs in fields such as sensors,bioimaging and energy Finally,the future development of C-GQDs is discussed from the perspectives of preparation methods,carbon source selection and research directions,and the following experimental schemes are proposed:(1)Experiment with H_(2)O_(2) as oxidizer and thermally altered coals as carbon sources;(2)Experiments other than oxidation with sulfuric acid and nitric acid using superhigh organic sulfur coals as carbon sources;(3)Experiment on coal macerals as a carbon sources.In addition,the combination of experimentally derived basic data and computer simulation technology can solve the problems of current research such as single fluorescence color and low quantum yield.The goals of clean utilization of coal resources and green development of GQDs have been achieved.