Silver nanoparticles as localized “nano-heaters” under LED light irradiation to improve membrane performance

Abstract

The possibility of improving the performance of solvent resistant nanofiltration (SRNF) membranes by the strategy of localized heating has been demonstrated in earlier work. The localized heating was realized by the plasmonic heating effect of gold nanoparticles (NPs) through incorporation of these “nano-heaters” into the membrane matrix. Heat is released from gold NPs to the membrane matrix under argon laser irradiation. Improved fluxes by laser irradiation without significantly lowering selectivities were achieved. This present study aims at using cheaper silver nanoparticles (AgNPs) with a cheaper and energetically more efficient LED light as an alternative for gold NPs with a laser device. Silver NPs were incorporated into different polymeric membranes, as confirmed by TEM images and UV-Vis spectra. The plasmonic heating effect on the performance of AgNP containing membranes was investigated by a dead-end filtration cell coupled to a 400 nm LED light irradiation. The influences of feed, polymer type, and AgNP preparation routes on the silver NP containing membrane performances under LED light irradiation were studied. The results indicate that AgNPs and LED light can be good alternatives for gold NPs and a laser device, rendering the whole approach more energy efficient, cheaper and less complicated.