黄色荧光碳点的合成及其双模式检测有机溶剂中水含量

Yellow-emitting carbon dots for colorimetric and fluorometric detection of water content in organic solvents

为了拓展荧光碳点在溶剂传感器领域的应用,我们采用以天然木质素为碳源,邻苯二胺为氮源,通过一步溶剂热法合成了黄色荧光碳点.获得的碳点尺寸在10 nm左右,形貌为圆盘状,并具有高的结晶性和石墨化程度.该碳点具有独特的发光特性:以水为溶剂,在紫外光激发下发出黄光,且具有激发独立性,此外,在不同溶剂中发出不同颜色的光.基于此,进一步将该碳点应用于溶剂传感器,特别是有机溶剂中水含量的检测.结果表明:该碳点不仅表现出基于发射波长变化的比色传感特性,而且还具有基于荧光强度变化的定量检测能力,可望实现有机溶剂中水含量的双模式传感,为高性能光学传感器的开发提供一种新思路.

To expand the applications of carbon dots(CDs)in solvent sensors,the yellow-emitting CDs(Y-CDs)had been created via one-step solvothermal synthesis based on lignin as the carbon source and o-phenylenediamine(OPD)as the nitrogen source.The Y-CDs had the size of 10 nm and showed plate-like morphology with high graphitization degree.The Y-CDs showed excitation-independent photoluminescence(PL)in different solvents and solvatochromic behavior,orange-yellow in water,yellow in ethanol,yellow-green in N,N-dimethyl formamide(DMF),and green in acetone.Based on this,The Y-CDs had been used as sensors for detection of water content in five organic solvents.On one hand,the Y-CDs could change their emission colors based on change of PL wavelength,for instance,from orange to yellow to green,offering a colorimetric sensing mode.On the other hand,the Y-CDs could change their PL intensities and had good linear relationship with the water content in organic solvents,providing a quantitative sensing mode.Thus,dual sensing strategies,including change of PL wavelength and intensities with water content in five organic solvents,were achieved simultaneously,showing great potential for the development of advanced optical sensors with high performance.