Effect of Fe-N Codoping on the Optical Properties of TiO2for Use in Photoelectrolysis of Water

Abstract

TiO2 nanoparticles were synthesized by green chemistry where organic solvents are replaced by an aqueous extract solution of lemongrass leaves that act as a reducer and growth-stopper agent. The nanoparticles were codoped with N-Fe to modify the absorption range in the electromagnetic spectrum and were characterized by Fourier-transform infrared (FTIR), scanning electron microscopy/energy dispersive X-ray spectroscopy (SEM/EDS), and UV-vis/diffuse reflectance spectroscopy (DRS). The modified samples with Fe and N resulted in smaller nanoparticle size values than pure TiO2. Similarly, the band-gap energy for doped nanoparticles decreased to 2.22 eV in relation to the value of 3.09 eV for pure TiO2, due to the introduction of new energy levels.