制备条件对PEI功能化石墨烯量子点荧光性能的影响

石墨烯量子点凭借其良好的水溶性、低生物毒性等特点,被不断尝试应用于生物成像领域,但其有限的荧光性能限制了其进一步应用。为改善石墨烯量子点的荧光性能以及进一步揭示石墨烯量子点的制备机理,本文对聚乙烯亚胺(PEI)功能化石墨烯量子点的制备条件进行了探索,讨论了不同反应时间、制备温度以及混悬液pH值对其荧光性能的影响。测试结果显示,当混悬液pH值为12时,在反应釜中经过200 ℃高温反应20 h,所制备的功能化石墨烯量子点能取得良好的紫外吸收峰和荧光性能,同时达到较高的量子产量。

Effect of Preparation Conditions on the Optical Properties of PEI-Functionalized Graphene Quantum Dots

Because of their low toxicity and excellent water-solubility, graphene quantum dots have been highly anticipated for use in cellular imaging. However, their limited optical properties are hampering this use. To address this issue, graphene quantum dots surface passivated by branched polyethylenimine (GQDs-BPEI) were proposed in this paper. We discussed optical properties when prepared under different conditions including reaction time, temperature, and pH value. The results indicate that GQDs-BPEI prepared at pH 12, at a temperature of 200 ℃, and with a 20 h reaction in an autoclave can achieve a higher UV absorbency and better PL properties with a high quantum yield.