Abstract
The current study reports the eco-friendly synthesis of titanium oxide and iron oxide (TiO2/alpha-Fe2O3) heterojunction using aqueous flax seed extract (FSE) as an alternative to hazardous chemicals, templates/surfactants and organic solvents, and utilizing the ultrasonic waves instead of high energy techniques. The use of antioxidants presents in the flax seed crop was explored to synthesize Fe2O3, TiO2 and Fe2O3/TiO2 with controlled morphology. The as-prepared materials were characterized by various techniques. Our results show the successful synthesis of TiO2 nanoparticles (11 nm), alpha-Fe2O3 nanospheres (100-300 nm) and Fe2O3/TiO2 nano composites in the presence of FSE. The as-prepared materials exhibited the highly crystalline structure and narrow size distribution with surface area up to 289 m(2)/g when compared to those produced in the absence of FSE. Thus, demonstrating the role of FSE as an effective templating and stabilizing agent to synthesize nanomaterials with controlled size and shape. The produced green nanomaterials showed enhanced photocatalytic performance in the visible region for the degradation of organic dye and excellent cycling properties as compared to their corresponding nanomaterials prepared with chemical method. The TiO2/alpha-Fe2O3 nanocomposites showed the best photocatalytic efficiency as compared to pure TiO2 or pure Fe2O3 nanomaterials, the activity was increased with increasing the amount of alpha-Fe2O3. This enhanced efficiency of the nanocomposite was attributed to increased energy harvesting ability, higher surface area and generation of electron-hole separation due to spatial electron transfer from alpha-Fe2O3 to TiO2 which prolonging the photogenerated charge carrier.