Efficient and continuous chemical conversion in a thin membrane comprising three-dimensional network trapping Ag nanoparticles

Abstract

In this work, we report a novel and highly efficient catalytic membrane (PES/PNM-Ag) comprising well-dispersed silver nanoparticles (NPs). The membrane can be straightforwardly constructed via dynamic loading expansible hybrid microgels PNM-Ag into a commercially-available poly(ether sulfone) (PES) membrane with asymmetric structure. Characterization results of PNM-Ag and PES/PNM-Ag indicate that a nanoscale three-dimensional network embedded with Ag NPs was developed in membrane pores by swollen microgels. The flat-sheet membrane reactor assembled with PES/PNM-Ag can efficiently and continuously catalyze the reduction of 4-nitrophenol (apparent reaction rate constant reaching 1.12 s−1) and showed good stability. The improved catalytic activity was attributed to fully accessible surface of Ag NPs as well as the unique structure of the membrane, in which the reactant was restricted to flow through immobilized catalyst. Present strategy hints to design other noble metal NPs loaded catalytic membranes for efficient conversion of nitro-aromatic pollutants.