Hierarchical mesoporous cobalt silicate architectures as high-performance sulfate-radical-based advanced oxidization catalysts

Shu-Meng Hao; Ming-Yuan Yu; Yu-Jiao Zhang; Yasmine Abdelkrim; Jin Qu

doi:10.1016/j.jcis.2019.03.017

Hierarchical mesoporous cobalt silicate architectures as high-performance sulfate-radical-based advanced oxidization catalysts

J Colloid Interface Sci. 2019 Jun 1:545:128-137. doi: 10.1016/j.jcis.2019.03.017. Epub 2019 Mar 7.

Authors

Shu-Meng Hao¹, Ming-Yuan Yu², Yu-Jiao Zhang¹, Yasmine Abdelkrim¹, Jin Qu³

Affiliations

¹ State Key Laboratory of Organic-Inorganic Composites, College of Materials Science and Engineering, Beijing University of Chemical Technology, Beijing 100029, China.
² Beijing No. 171 High School, Beijing 100013, China.
³ State Key Laboratory of Organic-Inorganic Composites, College of Materials Science and Engineering, Beijing University of Chemical Technology, Beijing 100029, China. Electronic address: qujin@mail.buct.edu.cn.

PMID: 30877996
DOI: 10.1016/j.jcis.2019.03.017

Abstract

Self-sacrificial biomass-derived silica is a rising and promising approach to fabricate large metal silicates, which are practical water treatment agents ascribed for easy sedimentation and separation. However, the original biomass architecture is difficult to be maintained and utilized. Furthermore, sufficient ion diffusion pathways need to be created to satisfy massive mass transport in large bulk materials. Herein, a series of metal silicates, including cobalt silicate (CoSiO_x), copper silicate, nickel silicate, iron silicate, and magnesium silicate, are synthesized from Indocalamus tessellatus leaf as the biomass-derived silica source and investigated as catalysts in sulfate-radical-based advanced oxidization processes (SR-AOPs) for the first time. Among them, CoSiO_x presents an analogical sandwich structure as a leaf-derived template of micron-level size. More importantly, the interior hollow nanotubes assembled by small nanosheets provide numerous pathways for ion diffusion and remarkably promote the mass transport in such large bulk materials. Owing to the combination of the unique structure with the high reactivity of Co (II) toward peroxymonosulfate, CoSiO_x exhibits excellent catalytic performance with 0.242 and 0.153 min^-1 rate constants for the removal of methylene blue and phenol, respectively, which outperforms/is comparable to that of the reported nanomaterials toward organic contaminants in SR-AOPs.

Keywords: Advanced oxidation processes; Biomass-derived silica; Cobalt silicate; Hollow nanotube; Sulfate radical.