Mesoporous reduction state cobalt species-doped silica nanospheres: An efficient Fenton-like catalyst for dual-pathway degradation of organic pollutants

作者：Zhang, Xuejian; Liang, Junrong; Sun, Yong; Zhang, Fagen; Li, Chenwei; Hu, Chun; Lyu, Lai^*

来源：Journal of Colloid and Interface Science, 2020, 576: 59-67.

DOI：10.1016/j.jcis.2020.05.007

• Heterogeneous Fenton
• Water purification
• Co-containing catalyst
• Dual-pathway degradation
• Electron donation of pollutants

A novel heterogeneous Co-containing Fenton-like catalyst consisting of mesoporous reduction state cobalt (RSCo)-doped silica (SiO2) nanospheres (mp-RSCo-SiO2 NSs) was prepared by an enhanced hydrothermal process. The catalyst exhibited very high activity and stability for a series of refractory pollutant degradation in a very wide pH range of 3.1-10.9. The Fenton-like reaction rate constant of this Co-containing catalyst was approximately 290 times higher than that of Co3O4 for pollutant degradation under the neutral and mild conditions. Based on the characterization, the catalyst possessed a porous nanosphere morphology, and the reduction state cobalt species, including nano-zero-valent cobalt (nZVCo) and Co2+, were found to be generated in the SiO2 framework through forming Co-O-Si bonds. During the Fenton-like reaction, the electron donation effect of organic pollutants was successfully realized through the interaction of "Pollutants -> Co2+/0-SiO2". The obtained electrons from pollutants were transferred to the catalyst surface and captured by H2O2, resulting in the generation of hydroxyl radicals ((OH)-O-center dot). Therefore, a dual-pathway degradation of the pollutants was realized: (I) oxidation and degradation as the electron donors for the system and (II) attacking and destruction by (OH)-O-center dot radicals. This work provided a new perspective on the effective utilization of the electrons of pollutants and the improvement of Fenton reaction efficiency.

• 单位
  哈尔滨工程大学; 广州大学