Citric acid was used as the carbon source, and three phenylenediamine isomers — o-phenylenediamine, m-phenylenediamine, and p-phenylenediamine — served as nitrogen sources to synthesize carbon quantum dots (CQDs) via a hydrothermal method. The resulting CQDs exhibited distinct colors: orange-yellow (o-phenylenediamine), light yellow (m-phenylenediamine), and purple (p-phenylenediamine). The CQDs were subsequently modified with oleylamine to introduce hydrophobic surface properties. Structural and optical properties before and after modification were characterized using Fourier transform infrared spectroscopy (FT-IR), fluorescence spectroscopy (FS), and ultraviolet-visible spectroscopy (UV-vis). The results indicate that the CQDs derived from m-phenylenediamine showed the most enhanced hydrophobicity after oleylamine modification, with significantly improved solubility in toluene, which is attributed to strengthened hydrocarbon interactions.

以柠檬酸为碳源, 分别以邻苯二胺、间苯二胺和对苯二胺为氮源, 采用水热法合成3种碳量子点(CQDs), 颜色分别为橘黄色(邻苯二胺)、淡黄色(间苯二胺)及香芋紫(对苯二胺)。随后, 通过油胺对CQDs表面进行疏水改性, 制得疏水性CQDs。利用傅里叶变换红外光谱(FT-IR)、荧光光谱和紫外可见光谱(UV-vis)等手段, 对改性前后的CQDs进行结构与性能表征。结果表明, 间苯二胺衍生的CQDs经油胺改性后, 其碳氢结构增强, 表现出最优的甲苯溶解性。