ZIF-67 grown on a fibrous substrate via a sacrificial template method for efficient PM2.5 capture and enhanced antibacterial performance

In the design air filtration materials, surface modification and porosity control are appealing strategies to achieve a higher quality factor. In this study, a sacrificial template method was introduced to obtain hierarchically metal-organic framework (MOF)-loaded micro/nano-backbone fibrous filters. Cobalt carbonate hydroxide hydrate nanoneedle arrays were first grown on polyester fabric as a sacrificial template that provide Co2+ source for constructing a ZIF-67 on micro/nano fibrous backbone substrate, which resulted in a combination of enokitake-like and bead-on-string-like structure simultaneously. This unique structure effectively reduced the pore size of the fabric and provided a modified surface with a maximum exposure of MOFs. As a consequence, the composite fabric filter exhibited excellent PM2.5 removal efficiency of 97.5 +/- 1.2%, while with only a small increase in pressure drop (similar to 14 Pa). Particularly, the PM2.5 filtration quality factor was up to 0.051, which is 200% higher than that of pristine PET. Furthermore, the composite fabric filter showed excellent antibacterial activity against both S. aureus and E. coli. This study facilitated the design of hierarchically MOF-loaded fibrous filter materials with excellent comprehensive filtration performance.