一步微波法合成碳点及其荧光性质研究

Study on the Fluorescence Properties of Carbon Dots Prepared by One Step Microwave Method

近年来合成水溶性的荧光碳点受到越来越多研究者的关注。相对于传统的镉基、硅基量子点和有机染料,碳点毒性低,性质稳定,可以进行化学修饰,并且可以和多种有机,无机,生物分子相容,在众多领域中得到广泛应用。以抗坏血酸为原料经过一步微波反应制备了荧光碳点。并通过X射线衍射(XRD),透射电镜(TEM),紫外-可见吸收光谱,荧光光谱,傅里叶红外光谱(FTIR)进行表征。结果显示以抗坏血酸为原料制备的碳点近似球形,大小均匀,分散性良好,无团聚现象,荧光强度大;表面富含羧基和羟基,发射波长依赖于激发波长,并且具有很强的亲水性。在pH 3～11的范围内具有良好的荧光性能。

In recent years, more and more researchers pay attention to the synthesis of water-soluble fluorescent carbon dots. Compared with the traditional cadmium-based, silicon-based quantum dots and organic dyes, carbon dots with low toxicity and high stability can be chemically modified and be compatible with a variety of organic, inorganic, and biological molecules, and can be applied in many areas. The fluorescence carbon dots were prepared by one step microwave method using ascorbic acid as raw materials. The carbon dots were characterized by X-ray diffraetion（XRD）, transmission electron mieroscopy（TEM）, ultraviolet-visible spectrophotometry, fluorescence spectrophotometry, and Fourier transform infrared spectrophotometry（FFIR）. The results showed that the carbon dots have approximate spherical morphology, uniform size, good dispersion and non-agglomeration, good fluorescence properties. The carbon dots were rich in carboxyl and hydroxyl groups and had highly hydrophilic nature. The emission wavelength of carbon dots depended on the excitation wavelength. Furthermore, these carbon dots also had good fluorescence properties in a wide pH range.