【作者】 路丹丹； 尹克样； 李洪光；

【Author】 Dandan Lu;Keyang Yin;Hongguang Li;Key Laboratory of Colloid and Interface Chemistry,Ministry of Education,Shandong University;

【机构】 山东大学胶体与界面化学教育部重点实验室；

【摘要】 零维碳点作为碳纳米材料家族中的一员,由于其独特的性质,受到了人们的广泛关注。有关碳点的应用开发也日益受到人们的重视。例如,Ma等人将制备的碳点掺杂到钙钛矿太阳能电池中以此来达到晶界钝化的目的,从而提高能量转换效率[1]。Mohammadid等人将钨酸盐离子固定于离子液体修饰的碳点,构筑了非均相纳米催化剂用于醇的氧化[2]。与其它发光材料相比,碳点表现出一些独特的性质,如激发波长依赖性。但目前关于碳点发光机理的确切解释还需进一步深化。一种观点认为碳点的表面官能团及表面缺陷引起了其荧光行为。除此之外,种种迹象表明碳点的制备条件,尤其是溶剂环境对碳点性质具有重要影响。目前已有一些非水溶剂中碳点制备的报道,如Rajender等人以N,N二甲基甲酰胺、二甲基亚砜和水为溶剂,合成了具有不同官能团的氧化石墨烯量子点并研究了其荧光性能[3]。但相比之下,碳点的非水相合成尤其是疏水碳点的制备相对比较滞后,需要进一步拓展。我们选择了邻二甲苯、间二甲苯、对二甲苯、邻二氯苯、对二氯苯、氯苯、溴苯、碘苯等多种非极性有机溶剂,以十二胺为碳源,通过热解回流的方法系统考察了不同溶剂在碳点制备过程中的影响,对所获得疏水碳点的发光机理进行了初步解释。同时采用硅胶柱层析的方法对所制备的碳点进行了分离纯化,得到了高纯度的碳点。更多还原

【Abstract】 As a member of the family of carbon nanomaterials, zero-dimensional carbon dots(C dots) have attracted extensive attention due to their unique properties. C dots have also been applied in various fields. For example, Ma et al doped C dots into perovskite solar cells to achieve the purpose of grain boundary passivation, thereby improving energy conversion efficiency[1]. Mohammadid et al fixed tungstate ions at the C dots modified by ionic liquids to construct heterogeneous nanocatalysts for the oxidation of alcohols[2]. Compared to other luminescent materials, C dots exhibit some unique properties, such as excitation wavelength dependence. However, the exact explanation of the mechanism behind the photoluminescence of C dots needs to be further elucidated. It is generally accepted that the photoluminescence of C dots is closely related to the functional groups and defects on the surface. In addition, evidence has gradually accumulated to show that the conditions where C dots were prepared, especially the solvent environment, have an important impact on the properties of C dots. At present, there have been some reports on the preparation of C dots in non-aqueous solvents. For example, Rajender et al synthesized graphene oxide quantum dots with different functional groups using organic solvents such as N,N dimethyl formamide and dimethyl sulfoxide and studied their fluorescence properties[3]. Even though, examples of C dots prepared in non-aqueous phases, especially the hydrophobic C dots, are still rare and need to be further expanded. In our work, decylamine was selected as the carbon source, which was then pyrolyzed in various nonpolar organic solvents such as o-xylene, m-xylene, p-xylene, o-dichlorobenzene, p-dichlorobenzene, bromobenzene and iodobenzene. The solvent effect on the preparation of C dots was investigated, and the luminous mechanism of the so-obtained hydrophobic C dots was discussed. Further, the prepared C dots were separated and purified by silica gel column chromatography, from which highly pure C dots were obtained.更多还原