Photodegradation of methylene blue by metal-nanoparticles-modulated-graphene-based composites: An efficient way of sewage water management

Abstract

Wastewater that holds a very high ratio of toxic contaminants, such as dyes and various organic compounds, from large cities is often pumped directly into rivers, seas, etc. without any treatment which leads to pollution and health hazards. Our work explains the enhanced degradation of dye by graphene oxide-based nanoparticles in the presence of sunlight. In this study, we describe how metal nanoparticles affect the photocatalytic activity of nanocomposites based on graphene oxide (GO). The hydrothermal method was used to create the Fe-doped GO@ZnO nanocomposites successfully. The different percentage of Fe ions doping inside the composites elicits methylene blue (MB) dye degradation efficiency. The catalytic activity of GO (32% in 1hr) is enhanced to 82% (in 1hr) for GO@ZnO composites. A further enhancement is achieved up to 99% after Fe doping inside the GO@ZnO composites. There is an increment of catalytic activity of GO@ZnO as the doping percentage of Fe increases. Interestingly the enhanced photocatalytic activity is not linear with the doping percentage of Fe. The highest activity is observed for 5% Fe doping. The degradation of MB is nearly 96% by the Fe-doped composites upon testing in the actual sample using river water. Thus, synthesized composite is a potential candidate for being an effective adaptable photocatalyst for removing organic dyes from wastewater because of its excellent stability and reusability.