化学学报 ›› 2022, Vol. 80 ›› Issue (5): 607-613.DOI: 10.6023/A22010018 上一篇    下一篇

研究论文

CdS基纳米管光催化氧化5-羟甲基糠醛选择性生成2,5-呋喃二甲醛

舒恒, 包义德日根, 那永*()   

  1. 哈尔滨工业大学化工与化学学院 哈尔滨 150001
  • 投稿日期:2022-01-11 发布日期:2022-05-31
  • 通讯作者: 那永
  • 基金资助:
    国家自然科学基金(21603046); 黑龙江省优秀青年基金(YQ2019B003)

Photocatalytic Oxidation of 5-Hydroxymethylfurfural Selectively into 2,5-Diformylfuran with CdS Nanotube

Heng Shu, Yide-Rigen Bao, Yong Na()   

  1. School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin 150001, China
  • Received:2022-01-11 Published:2022-05-31
  • Contact: Yong Na
  • Supported by:
    National Natural Science Foundation of China(21603046); Natural Science Foundation of Heilongjiang Province in China(YQ2019B003)

将生物质转化为高附加值化学品以替代传统化石能源衍生的碳资源不可再生能源已经引起了人们的广泛关注. 本工作制备了内部中空的ZnS@CdS/Ni纳米管催化剂用于光催化氧化5-羟甲基糠醛(HMF). 通过X射线光电子能谱表征了催化剂内部存在ZnS缺陷态使得ZnS能带带隙降低. 光照条件下, 光生空穴能够从CdS迁移至ZnS缺陷态, 抑制了ZnS@CdS内部的载流子复合, 提高了光催化性能. 中空的纳米管表面负载Ni催化剂可以参与质子还原产氢的反应, 而ZnS@CdS内部产生的空穴可以催化氧化HMF选择性生成2,5-呋喃二甲醛(DFF). 光反应1 h后, HMF的转化率达到36%, 产物DFF选择性为99%, 并且催化剂可以重复利用三次而不降低催化效果.

关键词: 生物质, 5-羟甲基糠醛, 2,5-二甲酰基呋喃, 光催化, 硫化镉

Conversion of 5-hydroxymethylfurfural (HMF) into high value-added chemicals to take place of carbon resources relying on non-renewable fossil reserves has attracted much attention in recent years. Besides, in a system of water splitting for hydrogen production, HMF oxidation can be incorporated to provide electrons instead of the kinetically sluggish water oxidation. In this paper, hollow ZnS@CdS/Ni nanotubes were prepared for photocatalytic oxidation of HMF coupled by catalytic hydrogen generation. ZnO was employed as template to form ZnO@ZnS@CdS first. The ZnO template was removed in the presence of strong basic solution. Due to the excess of S2- used, ZnS defect state exsited in ZnS@CdS, which was confirmed by ultraviolet-visible (UV-Vis) spectroscopy and X-ray photoelectron spectroscopy (XPS). The ZnS defect state had no effect on the conduction band edge potential of ZnS but reduced the band gap of ZnS. In combination of the absorption edge and the electrochemical measurements, the potentials for valence band edges of CdS and ZnS defect state were determined, respectively. Under light irradiation, the photogenerated electrons could be accumulated on the surface of CdS, and the photogenerated holes could migrate from CdS to ZnS defect, reducing the carrier recombination and improving the photocatalytic performance. With further deposition of Ni nanoparticles on the surface of CdS nanotube, the ZnS@CdS/Ni structure could accomplish the oxidation of HMF into 2,5-diformylfuran (DFF) selectively and hydrogen production at the both reaction sites. Under optimal amount of the Ni deposition, conversion of 36% for HMF oxidation was accomplished by ZnS@CdS/Ni-30 after 1 h photo reaction. At this stage, DFF as the main product with selectivity of 99% was obtained. Besides, H2 was detected in the head space of the reaction system, suggesting that HMF can be functioned as electron donor in stead of an H2O molecule in photo water splitting. The photo-generated holes were found to be the active species for the conversion of HMF into DFF. Under optimal photo reaction time (1 h), the prepared catalyst can be recycled three times without obvious decrease in catalytic activity. And the X-ray diffraction (XRD) pattern for the catalyst after photo reaction kept similar to that before reaction.

Key words: biomass, 5-hydroxymethylfurfural, 2,5-diformylfuran, photocatalysis, cadmium sulfide