Acta Chim. Sinica ›› 2019, Vol. 77 ›› Issue (7): 653-660.DOI: 10.6023/A19040113 Previous Articles     Next Articles

Article

具有分级纳米结构的In2S3/CdIn2S4在可见光下催化苯甲胺的氧化偶联反应

刘茹雪a, 何小燕b, 牛力同a, 吕柏霖a, 余菲a, 张哲a, 杨志旺a   

  1. a 西北师范大学 化学化工学院 生态环境相关高分子材料教育部重点实验室;保水化学功能材料甘肃省国际科技合作基地 兰州 730070;
    b 平凉市第七中学 甘肃平凉 744000
  • 收稿日期:2019-04-04 出版日期:2019-07-15 发布日期:2019-06-05
  • 通讯作者: 杨志旺 E-mail:yangzw@nwnu.edu.cn
  • 基金资助:

    项目受国家自然科学基金(No.21563026)、教育部“长江学者和创新团队发展计划”(No.IRT15R56)和甘肃省基础研究创新群体计划项目(No.1606RJIA324)资助.

Hierarchical In2S3/CdIn2S4 Heterostructured Nanohybrids as Photocatalyst for Coupling of Benzyl Amines under Visible Light

Liu Ruxuea, He Xiaoyanb, Niu Litonga, Lv Bolina, Yu Feia, Zhang Zhea, Yang Zhiwanga   

  1. a College of Chemistry and Chemical Engineering, Northwest Normal University Key Laboratory of Eco-Environment-Related Polymer Materials, Ministry of Education Gansu International Scientific and Technological Cooperation Base of Water-Retention Chemical Functional Materials, Lanzhou 730070;
    b Pingliang No.7 Middle School, Gansu Pingliang 744000
  • Received:2019-04-04 Online:2019-07-15 Published:2019-06-05
  • Supported by:

    Project supported by the National Natural Science Foundation of China (No. 21563026), the Program for Changjiang Scholars and Innovative Research Team in University (No. IRT15R56), and the Innovation Team Basic Scientific Research Project of Gansu Province (No. 1606RJIA324).

It is a more attractive strategy that the selective oxidation of amines to the corresponding imines driven by visible light and photocatalyst. However, it is still necessary to look further into the mechanism of the transformation. In order to advance a new green photocatalysts system under milder conditions, hierarchical In2S3 nanotubes, which maintained the mother skeleton of NH2-MIL-68(In), was prepared from NH2-MIL-68(In) and thiourea, and a cation exchange method was used to synthesize hierarchical In2S3/CdIn2S4 heterostructured composites. The structure, morphology and photoelectric properties of the catalysts were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), ultraviolet-visible diffuse reflectance spectroscopy (UV-vis DRS), fluorescence spectroscopy (PL) and electrochemical impedance spectra (EIS) analysis. The results showed that the existence of heterojunction between In2S3 and CdIn2S4 could minimize the recombination rate of photogenerated electron-hole pairs, which made the In2S3/CdIn2S4 show superior catalytic activity. The results of the evaluated experiments under visible light illumination showed that lots of synergy existed between the hierarchical structure, and the heterostructure could help to enhance the efficiency of carriers transfer and separation, which resulting in a high photocatalytic efficiency of In2S3/CdIn2S4 nanohybrids for the oxidation coupling of benzyl amines to imines under visible light irradiation. Interestingly, the further investigation concerned to the reaction condition revealed that the product could be detected not only in air but also in N2 conditions, which burst out of the restriction of the reported reaction conditions and made the condition of the conversion become milder. The possible photocatalytic mechanism for the transformation was investigated by a series of experiments which concerned to the catching of the active species. The results showed that the reason for the occurring of the reaction was initiated by the presence of the nitrogen-centered radical cations and the carbon-centered radicals which were induced by the photogenerated hole (h+) in the photocatalyst. As for these situations, the conditions for the conversion of benzyl amines to imines were milder than the reported ones ever. What's more, from our experiments, the catalysts can be recycled five times at least, which indicated good reusability of hierarchical In2S3/CdIn2S4 nanohybrids.

Key words: NH2-MIL-68(In), hierarchical structure, visible-light photocatalysis, coupling of benzyl amines, heterostructure