Scavenging of organic pollutant and fuel generation through cost-effective and abundantly accessible rust: an economical approach for waste management and energy generation

At present, wastes management and energy generation are the foremost concerns due to their direct relationship with the biological species and environment. Herein we report utilization of iron rust (inorganic pollutant) as photocatalyst for photodegradation of methylene blue (MB) dye (organic pollutant) under visible light (economic) and water oxidation (energy generation). Iron rust was collected from metallic pipes and calcined in the furnace at 700 °C for 3 h in order to remove moisture/volatile content. The uncalcined and calcined Rust are characterized through scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and Fourier transform infrared (FTIR) analysis, X-Ray Diffraction (XRD) and Thermogravematric analysis (TGA). The morphological study illustrated that the shape of uncalcinedand calcined iron rust is spongy, porous, and agglomerated. The XRD and DLS particle size is in a few hundred-nanometer range.The photodegradation (PD) investigation shows that calcined Rust is a potent photocatalyst for the PD of modeled MB and degraded about 94% in a very short time of 11 min. The photoelectrochemical (PEC) measurements revealed that calcined Rust is more active than uncalcined Rust under simulated 1-SUN illumination with respective photocurrent densities of ~0.40 and ~0.32 mA/cm2. These results demonstrate that cheaper and abundantly available Rust can be a useful candidate for environmental and energy applications.