Preparation of multifunctional cellulosic fabric based on graphene/TiO2 nanocoating

Abstract

Photocatalysts in powder form commonly cannot have a high photocatalytic efficiency without strong agitation in traditional photocatalytic process. It is also inconvenient for recovery of the photocatalysts in powder form after usage. This consequently, results in a secondary pollution which limits their application in water treatment for heavily polluted natural waterways. In this work, coating GO and TiO2 nanomaterials over large-scale cellulose substrates which can easily float on water was performed in the presence of crosslinker by applying a simple dip-coating method. The photocatalytic activities were evaluated by studying the degradation of two models of organic pollutants, methylene blue and glyphosate under visible light irradiation. The nanomaterial wrapped substrates endured over 40 times reuse at an optimum photocatalyst concentration of 0.1 g/L GO and 15% TiO2 based on fabric weight. The highest degradation rate was obtained at this point and a further increase in concentration decreased the degradation rate. The efficient degradation of glyphosate by the nanomaterial loaded substrate confirms its industrial application in treating pesticide and herbicide polluted waters. Remarkably, this study has established a feasible practical way for direct degradation of pollutants in lakes or rivers using mechanically floating large-scale cellulose-supported photocatalysts.