温敏型碳点的新法合成

New microwave synthesis of temperature sensitive carbon dots

用柠檬酸和聚乙二醇200为原料,通过微波法制成了碳点溶液,利用IR、XRD、UV、TEM、激光动态光散射和荧光分光光度计进行了表征.实验结果表明,该法制备的碳点近似球形,粒径约为5nm,分散均匀,无团聚现象,在363nm的最佳激发波长处,发射波长为418nm.随着所制得的碳点溶液温度的升高,发射峰位置不发生移动,而荧光强度呈十分显著的下降趋势,并且温度与荧光强度呈较好的线性关系,R2=0.9895.这种对温度敏感的碳点,有望用于温敏碳点荧光材料显示与测量表面温度的装置中.

The carbon dots solution was prepared by the microwave method using citric acid and polyethylene glycol 200 as raw materials, which was characterized by laser dynamic light scattering, XRD, UV, TEM and fluorescence spectrophotometer. The experimental results show that the carbon dots produced are approximate spherical with better dispersity and without reunion phenomenon, and their sizes are about 5 nm. At the optimum excitation wavelength of 363 nm, the emission wavelength is 418 nm. With the increase of temperature, the emission peak position of the carbon dots solution does not move, but the intensity of fluorescence declines significantly. There is a good linear relationship between the fluorescence intensity and temperature, R^2 =0.9895. The carbon dots sensitive to temperature are expected to be used in some devices of fluorescent material of displaying and the measurement of surface temperature.