Synergistic effects of doping, composite formation, and nanotechnology to enhance the photocatalytic activities of semiconductive materials

Abstract

Graphene, the promising carbon allotrope, has recently gained substantial research attention due to its unique physiochemical properties and distinctive 2D structure. Graphene-based composites have remarkable electronic and crystal properties and have emerged as promising photocatalysts owing to their greater surface area, superior adsorption, and charge transfer capacity. In this study, we made indium-doped molybdenum trioxide (In–MoO3) nanobelts. We combined them with nanosheets of reduced graphene oxide (rGO) to create a new photocatalyst for removing organic compounds (textile colors) from industrial waste. The prepared materials' surface morphology, crystalline structure, functional group detection, light absorption capacity, and electrochemical behavior have been investigated and validated using well-established characterization techniques. We examined the photocatalytic activity of freshly produced catalysts under the same circumstances by mineralizing the MB dye. The rGO/In–MoO3 composite outperformed pure MoO3 and In–MoO3 samples in photo-mineralization activity. After being exposed to light for one hundred minutes, the rGO/In–MoO3, In–MoO3, and MoO3 photocatalysts removed approximately 96%, 64%, and 49% of the MB dye, respectively. According to the reaction kinetics, the rGO-supported In–MoO3 sample removed the dye at a rate of 0.0250/min. This rate was 2.43 and 4.03 times higher than the rate that was attained by the samples that consisted just of bare MoO3 and In–MoO3, respectively. In chronoamperometric analysis, the rGO/In–MoO3 catalyst showed a 4.68 and 1.65-fold higher transient photocurrent response than the MoO3 and In–MoO3 catalysts, respectively. The synergistic properties of the significantly conducting graphene matrix and nanoscaled In–MoO3 were primarily responsible for the rGO/In–MoO3's improved photomineralization performance. These effects increased the separation of e−-h+ and improved the light-harvesting capacity. This new research shows a practical way to make highly effective photocatalysts that can be used in wastewater treatment in industry.