Multifunctional g-C3N4/Ag NPs intercalated GO composite membrane for SERS detection and photocatalytic degradation of paraoxon-ethyl

Pesticide residues in the aquatic environment pose a threat to ecological environment and human health. The considerable concerns make it necessary to develop efficient strategies for the detection and degradation of pollutants. In this work, a multifunctional membrane was fabricated on the self-assembly of graphene oxide nanosheets with g-C3N4 and Ag NPs intercalated. The prepared GO/g-C3N4/Ag membrane exhibits high enrichment ability for small molecules, which is beneficial to the detection of organic pollutants at low concentrations. It also exhibits excellent SERS sensitivity and photocatalytic activity. Paraoxon-ethyl at nM-level concentrations can be detectable and then degraded almost completely under visible-light irradiation. The high SERS activity can be ascribed to the integration of enrichment ability of GO and surface plasmonresonance (SPR) of Ag NPs. And the photocatalytic mechanism was proposed as the improved separation efficiency of photo-generated electron-hole and the production of active radicals. Through a facile method, this work presents a highly active multifunctional membrane towards simultaneous detection and degradation of low-concentration organic pollutants.