氮修饰荧光碳量子点的光学性能研究

Optical Properties Study on Nitrogen-modifi ed Fluorescent Carbon Quantum Dots

本文分别以柠檬酸和不同量的氨水(1mL、2mL、3mL)为C源和N源,通过水热反应法成功制备了氮含量不同的氮修饰碳量子点(CQDs-N1、CQDs-N2和CQDs-N3),并对其光学性能进行了研究。结果表明,制备的CQDs-N颗粒尺寸大约在2~4nm之间,存在较明显的指纹状晶格条纹,可以发射出蓝色荧光。同时N含量的提升可以有效提高CQDs-N对紫外光的吸收强度和荧光发射强度,其光学稳定性也随之提升。CQDs-N1溶液适用于中性或弱碱性环境(pH=7~9),光老化试验表明纳米二氧化硅的引入并不会改变CQDs-N的结构,但会使老化速率降低,增强CQDs-N溶液的光稳定性。

In this paper,the nitrogen-modified carbon quantum dots with different nitrogen contents(CQDs-N1、CQDs-N2和CQDs-N3)were obtain by a hydrothermal reaction method using citric acid and ammonia(with different volume 1mL,2mL,3mL)as carbon and nitrogen sources,and their optical properties were studied.The results show that the size of prepared CQDs-N particles are between 2~4 nm,fingerprint-like lattice fringes were investigated obviously and with blue fluorescence emission.Meanwhile,the increased N content can effectively improve the absorption intensity and fluorescence emission intensity of CQDs-N at ultraviolet light region,the optical stability were also improved significantly.The CQDs-N1 solution is suitable for neutral and weak alkaline environment(pH=7~9),photo-aging test shows that the introduction of nano-silica will change the structure of CQDs-N not only,but also reduce the aging rate and enhance the photostability of the CQDs-N solution.