核壳结构CdS@C纳米复合材料的光催化性能研究

摘要/Abstract

摘要： 采用水热碳化法成功制备了不同碳含量的CdS@C纳米颗粒,同时对CdS@C的晶体结构、形貌、光学性能、光电化学和光催化性能进行了研究。实验结果表明本方法制备的碳包覆CdS纳米颗粒外壳为碳层,内核为六方纤锌矿结构CdS颗粒。CdS@C颗粒分散性良好,颗粒形貌主要为类球形,粒度均匀。X射线光电子能谱(XPS)证实CdS@C颗粒表面负载的碳主要以非晶碳形式存在。紫外-可见光光谱(UV-Vis)表明CdS@C纳米晶中表面碳的敏化作用提高了可见光响应范围,使得能隙变窄。光致发光光谱(PL)表明碳包覆CdS@C纳米颗粒的发光强度比纯CdS弱,有效抑制了光生载流子的复合。瞬态光电流响应和电化学阻抗谱(EIS)说明CdS@C纳米复合材料更有效促进电子-空穴对分离和提高转移效率。CdS@C纳米复合材料在可见光辐射下表现出良好的光催化活性和稳定性,其中·O₂^-和h⁺在光催化中起主要作用。

关键词: 碳包覆, CdS, 核壳结构, 光电化学性能, 光催化, CdS@C纳米复合材料

Abstract: CdS@C nanoparticles with different carbon content were successfully prepared by hydrothermal carbonization method, and the phase structure, morphology, optical, photoelectric chemistry and photocatalytic properties of CdS@C were studied. The experimental results show that the shell is successfully prepared as carbon layer, and the hexahedrite structure CdS is used as CdS@C particles in the core. The morphology of CdS@C particles is mainly spherical, with uniform particle size and good dispersion. XPS spectra confirm that the carbon loading on the surface of CdS@C particles mainly existe in the form of amorphous carbon. UV-Vis spectra show that the sensitization of surface carbon in CdS@C nanocrystals increase the visible light response range and narrowed the energy gap. PL show that the luminescence intensity of carbon-coated CdS@C nanoparticles is weaker than that of pure CdS, which effectively inhibited the electron-hole pair recombination. Transient photocurrent response and electrochemical impedance spectroscopy (EIS) indicate that CdS@C nanocomposite have a good optical response and show more efficient photocarrier separation and transfer efficiency. CdS@C nanocomposite exhibites good photocatalytic activity and stability under visible light radiation, and ·O₂^- and h⁺ play major roles in photocatalysis.

Key words: carbon-encapsulated, CdS, core-shell structure, photoelectric chemistry, photocatalytic, CdS@C nanocomposite

中图分类号:

张克诚, 马强, 王健, 马龙, 卢强, 韦琪龙, 魏智强, 乔宏霞. 核壳结构CdS@C纳米复合材料的光催化性能研究[J]. 人工晶体学报, 2020, 49(12): 2336-2343.

ZHANG Kecheng, MA Qiang, WANG Jian, MA Long, LU Qiang, WEI Qilong, WEI Zhiqiang, QIAO Hongxia. Photocatalytic Properties of Core-Shell Structure CdS@C Nanocomposites[J]. JOURNAL OF SYNTHETIC CRYSTALS, 2020, 49(12): 2336-2343.

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