Mixed-dimensional assembled superhydrophilic graphene-based aerogel with enhanced mass/charge transportation for efficient photoredox catalysis

Abstract

Photocatalysis is a promising method for environment remediation, such as organic pollutant degradation, disinfection and heavy metal ion reduction, while the light adsorption limitation, photo-induced charge carrier recombination and insufficient surface catalytic reaction has restricted its practical application. Here in this work, a highly hydrophilic wood derived cellulose nanofibril (CNF) was firstly introduced into α-FeOOH/reduced graphene oxide (rGO) aerogel system through a simple self-assembly method. In this composite system, the rGO acting as an electron transfer and the CNF acting as a hole sink, this dual charge transfer channel can maximize the charge carrier separation efficiency, meanwhile, the as obtained α-FeOOH/CNF/rGO aerogel has shown great enhanced water affinity-superhydrophilicity, which can sufficiently enhance the mass transportation during photocatalysis activity, the simultaneously enhancement of interfacial charge/mass transportation has endowed this photocatalytic system with both excellent photocatalytic oxidation and reduction performance. Under visible light irradiation, α-FeOOH/CNF/rGO can realize efficient degradation of various organics including dyes, aromatic compounds and antibiotics, killing bacterial as well as reduction of heavy metal ion. The simple, low-cost and environmentally friendly fabrication method along with excellent performance of this catalyst indicate its great application prospect for environmental protection.