2D N-doped graphene/CoFe MOFs heterostructure functionalized CNF aerogels impart highly efficient photocatalytic oxidation of gaseous VOCs

Abstract

Developing efficient photocatalysts for degrading volatile organic compounds (VOCs) has aroused great interest. Herein, the 3D composite aerogel catalysts (CLGM-A) with cellulose nanofibers (CNF) skeleton-supported 2D CoFe bimetallic metal-organic frameworks (2D CoFe MOFs) and 2D N-doped graphene (2D N-GE) heterostructures were prepared by freeze-drying and were successfully applied to the photocatalytic degradation of toluene. With 2D–2D (face-contact) heterojunction, the separation efficiency of photo-generated electron-hole pairs was significantly improved by the rapid transfer of electrons and inhibition of electron backflow on the N-GE/2D CoFe MOFs (GM) during the photocatalytic process. As a result, the CLGM-A achieved 95.4% toluene removal in 120 minutes, 83.6% mineralization efficiency, and demonstrated good stability and reusability in continuous cycle tests. Radical analysis suggested that •O2- was the main active species produced in the CLGM-A system, which could realize the efficient degradation of volatile organic pollutants at room temperature.