黄色荧光碳点的制备及LED应用

Synthesis of Yellow Fluorescent Carbon Dots and Their Application in LED

以3,4-二氨基苯甲酸为前驱体,乙醇作溶剂,通过一步溶剂热法制备具有黄色荧光的碳点。高分辨透射电子显微镜和拉曼光谱表明碳点是平均尺寸3nm左右,具有一定石墨结构的纳米颗粒。元素和表面基团分析表明碳点表面存在丰富的羟基、羧基等官能团,具有良好的溶解性。荧光光谱表明该碳点最适激发波长为380nm,荧光发射波长为540nm,具有激发波长独立性;以罗丹明B作为参比,测得碳点的相对荧光量子产率高达67%。利用碳点同聚乙烯醇复合,固态薄膜同样表现出优异的荧光稳定性。可替代传统荧光粉用于紫外芯片式LED,在光电领域有较好的应用前景。

3,4-diaminobenzoic acid was used as the precursor to prepare the carbon dots with yellow fluorescence(YCDs)by one-step solvothermal method.High-resolution transmission electron microscopy(TEM)and Raman spectroscopy indicate that the Y-CDs are nanoparticles with an average size of about 3 nm and graphite structure.The elements and surface groups indicate that the Y-CDs have abundant functional groups such as hydroxyl groups and carboxyl groups on the surface and good solubility.Fluorescence spectroscopy indicates that excitation wavelength of Y-CDs locates 380 nm,and fluorescence emission wavelength is 540 nm,and excitation wavelength is independent.With Rhodamine B as a reference,the relative fluorescence quantum yield of Y-CDs is as high as 67%.Polyvinyl alcohol film with Y-CDs doped also exhibits excellent fluorescence stability.The superb fluorescence characteristics of Y-CDs can replace the traditional phosphor for Light-emitting diodes,and have a good application prospect in the field of optoelectronics.