生物质基碳量子点的制备及其光谱性质研究

Preparation of Carbon Quantum Dots by Biologic Matters and Its Spectrum Properties

以木屑为前驱物制备的活性炭为碳源,采用化学氧化法,用聚乙二醇2000进行表面钝化,制备出了水溶性的生物质基碳量子点。优化了CQDs的合成方法:0.3 g生物质基活性炭,40 mL HAc-80 mL 30%H2O2混合氧化剂,反应温度为100℃,反应时间为12 h。采用微波和超声结合法进行钝化,修复了CQDs的表面缺陷,荧光强度和量子产率均得到了提高。采用透射电子显微镜、紫外-可见吸收光谱仪、荧光分光光度计和傅里叶红外分光光度计进行表征,所合成的碳量子点发光性能优异、粒径小、分散性好,且无团聚现象。进一步考察了光照、温度和体系pH值对碳量子点性能的影响,结果表明,光稳定性好,抗光漂白性优异,荧光强度具有pH值依赖性,且易于表面功能化。

Using activated carbon prepared by sawdust and PEG2000 as surface coated agent,water-soluble carbon quantum dots were synthesized by chemical oxidation method.The method of synthesis of CQDs was optimized.The optimed synthesis condition of CQDs was 0.3 g of standast activated carbon,the mixed oxidant of 40 mL HAc-80 mL 30% H2O2,at the temperature of100 ℃ for 12 h.In order to repair the surface defect of CQDs,a passivation treatment is perfermed using ultrasonic and micromave methods.The structures and optical properties of the obtained CQDs were characterized by transmission electron microscope（ TEM）,Ultraviolet-Visible（ UV-Vis） spectroscopy,photoluminescence（ PL） spectroscopy and Fourier transform infrared spectrophotometer（ FT-IR）.The prepared CQDs feature the excellent optical performance and high dispersion without agglomeration.The effects of ambient temperature,light and pH value on the property of CQDs were studied.Experimental results show that CQDs have lots of advantages,such as good stability,excellent anti-light bleaching,pH value dependence and feasible surface functionalization.