Ag-decorated PP nonwoven for excellent catalytic reduction of 4-nitro-phenol and antibacterial study

Silver particles have been frequently coated on the surface of substrates with the assistance of polydopamine due to their important catalytic and antibacterial properties. However, the polydopamine layer was not compact and the resulted particles on the substrates were easy to leak during the application process, especially in the aqueous environment. For mediating this, we coated Ag particles on the surface of polypropylene (PP) nonwoven fabric by codeposition of catechol and polyethyleneimine, with subsequent crosslinking by glutaraldehyde. The for-mation of Ag particles on PP nonwoven fabric surface was systematically characterized using SEM, EDS and elemental mapping, TEM, FTIR, XRD and TG. Batch experiment showed that Ag@PP nonwoven fabric could effectively degrade the model pollutant 4-nitrophenol in the presence of reduction agent NaBH4 with 100% degradation efficiency. The adsorption isotherm was assessed and displayed that the sorption of 4-nitrophenol on reactive Ag@PP nonwoven fabric followed the Freundlich model. The Ag@PP nonwoven fabric was easy to be recycled and could maintained 100% degradation efficiency after six cycles. The degradation process was monitored using HPLC/MS and the possible degradation mechanism was proposed. In addition, the Ag@PP nonwoven fabric showed excellent antibacterial activity against E. coli. Overall, the material fabricated in this work would be a reusable catalyst for water purification and disinfection.

Automated summary

Silver particles have been frequently coated on the surface of substrates with the assistance of polydopamine due to their important catalytic and antibacterial properties. However, the polydopamine layer was not compact and the resulted particles on the substrates were easy to leak during the application process, especially in the aqueous environment. For mediating this, we coated Ag particles on the surface of polypropylene (PP) nonwoven fabric by codeposition of catechol and polyethyleneimine, with subsequent crosslinking by glutaraldehyde. The Ag@PP nonwoven fabric exhibited efficient degradation of 4-nitrophenol and excellent antibacterial activity against E. coli.