硫氮共掺杂碳量子点的制备及应用

Preparation and Application of Sulfur and Nitrogen Co-doped Carbon Quantum Dots

以中性红和硫脲为原料,一步水热法制备了近红外荧光硫氮共掺杂碳量子点(SN-CQDs)。通过透射电子显微镜(TEM)、紫外-可见吸收光谱、荧光光谱、X射线光电子能谱等技术对制备的SN-CQDs进行形貌及光学性质表征。制备的SN-CQDs尺寸均匀,稳定性高,在荧光光谱中,发射波长最大值在628 nm处,最佳激发为510 nm。铬离子(Cr3+)和4-硝基酚(4-NP)对SN-CQDs产生荧光猝灭作用,且具有良好的选择性,将制备的SN-CQDs作为荧光探针用于Cr3+和4-NP的检测。Cr3+浓度在0~170μmol/L范围内与SN-CQDs的荧光猝灭程度呈现良好的线性关系,相关系数为0.9922。4-NP的浓度在0~240μmol/L范围内与SN-CQDs的荧光猝灭程度呈现良好的线性关系,相关系数为0.9955。制备的碳量子点用于实际水样检测准确度较高,对Cr3+和4-NP具有高灵敏度以及较好的抗干扰能力,为检测Cr3+、4-NP提供了新的检测方法。

Sulphur and nitrogen co-doped carbon quantum dots(SN-CQDs)were synthesized by one-step hydrothermal method using neutral red and thiourea as raw materials.The morphology and optical properties of the synthesized CQDs were characterized by transition electron microscopy(TEM),ultraviolet,X-ray photoelectron spectroscopy(XPS)and fluorescence techniques.The synthesized SN-CQDs have uniform size and high stability.In the fluorescence spectrum,the maximum emission wavelength is 628 nm,and the maximum excitation wavelength is 510 nm.Chromium ions(Cr3+)and 4-nitrophenol(4-NP)have a fluorescence quenching effect on SN-CQDs.Using SN-CQDs as fluorescent probes for Cr3+,4-NP detection,the Cr3+concentration in the range of 0~170μmol/L has a good linear relationship with the fluorescence quenching degree of SN-CQDs,and the correlation coefficient is 0.9922.The concentration of 4-NP in the range of 0~240μmol/L shows a good linear relationship with the fluorescence quenching,and the correlation coefficient is 0.9955.In the actual water sample detection,the SN-CQDs has high accuracy,high sensitivity and good anti-interference ability to Cr3+and 4-NP detection.This work provides a new detection method for Cr3+and 4-NP.