A strategy for constructing highly efficient Co3O4-C@SiO2 nanofibers catalytic membrane for NH3-SCR of NO and dust filtration

Abstract

The strategy of constructing catalytic membrane has a significant influence on its structure and performance. In this work, Co3O4-Cx@SiO2 nanofiber membranes (NFMs) were fabricated by an in-situ growth–pyrolysis–oxidation strategy. The Co3O4-Cx catalyst derived from ZIF-67 was wrapped around nanofibers, which helps to maintain a stable membrane structure, then suppressing the reduction of gas permeability. Among the Co3O4-Cx catalyst, the carbon skeleton can prevent the agglomeration of Co3O4 nanoparticles, obtaining an ultra-fine Co3O4 nanoparticles with high dispersibility, redox property and surface area. The obtained Co3O4-C300@SiO2 NFM exhibits outstanding ammonia selective catalytic reduction (NH3-SCR) denitrification activity (T90 = 225 °C at a GHSV of 77,000 h−1). The effect of catalyst loading on PM2.5 filtration performance of SiO2 NFM was also tested. Co3O4-C300@SiO2 NFM has higher filtration efficiency (99.99%) than SiO2 NFM at a lower pressure drop of 58 Pa, which suggests that catalyst loading via our method can improve the filtration performance of SiO2 NFM. This work might provide a universal strategy for the design and preparation of highly efficient catalytic membrane.