碳量子点磁性纳米复合材料的制备与表征

Preparation and characterization of magnetic nanocomposite of carbon quantum dots

采用一步法在高压反应釜中合成了粒径均一、荧光性能优异的碳量子点(CQDs)。再以化学共沉淀法制备纳米Fe_3O_4粒子,通过聚多巴胺(PDA)修饰制备得Fe_3O_4/PDA。本实验首次以PDA为桥梁,将Fe_3O_4纳米颗粒与CQDs连接,合成了以CQDs为荧光材料的多功能复合微球Fe_3O_4/PDA@CQDs。经过傅里叶变换红外光谱仪、X射线衍射、振动样品磁强计、透射电子显微镜及荧光分光光度计等对该纳米复合物表征。结果表明:CQDs粒径约10nm,连接后的复合纳米粒子粒径在40nm左右,分散性良好且兼具优异的磁响应性和荧光发光性能。该复合微球无毒且生物相容性高,可以取代半导体量子点磁性纳米复合材料并广泛应用于药物分离、可视化和靶向治疗等生命科学领域。

The carbon quantum dots with uniform particle size and excellent fluorescence were synthesized by one step method in the condition of high pressure reaction kettle.Fe_3O_4 nanoparticles prepared by coprecipitation were modified by poly dopamine（PDA）,Fe_3O_4/PDA microspheres were obtained.Fe_3O_4 nanoparticles were connected with carbon quantum dots by poly dopamine for the first time.Multifunctional composite microspheres Fe_3O_4/PDA@CQDs were synthesized,which regarded carbon quantum dots as fluorescent materials.The nanocomposites were characterized by fourier transform infrared spectroscopy（FT-IR）,X-ray diffraction（XRD）,vibrating sample magnetometer（VSM）,transmission electron microscopy（TEM）and fluorescence spectrophotometer.The results showed that the particle diameter of carbon quantum dots was about 10 nm,the size of composite nanoparticles was about 40 nm.More importantly,the nanoparticles had good dispersion,excellent magnetic response and fluorescence.The magnetic nanocomposite of carbon quantum dots had no toxicity and high biocompatibility,which can replace the magnetic nanocomposite of semiconductor quantum dots and be applied in the field of life science,such as medicine separation,visualization,targeted therapy and so on.