Solar Energy, Vol.182, 332-339, 2019
Hydrothermal syntheses of Vanadium doped alpha - Fe2O3 cubic particles with enhanced photoelectrochemical activity
Water splitting to produce hydrogen using semiconductor material has been a focus of intense research in last few years. The main challenge to accomplish this task is to find a suitable band gap, non-toxic and earth abundant material for photoelectrochemical (PEC) process. alpha - Fe2O3 is proven to be a suitable candidate for PEC process because of its stability, non-toxic nature, abundance is nature and a narrow band gap of (1.9-2.2 eV). In this work V-doped alpha - Fe2O3 cubic particles were deposited on ITO substrate by hydrothermal and annealing method. The composition of V was controlled in bath solution by changing the concentration of V from 0 to 3%. After successful deposition, all samples were characterized by structural studies using x-ray diffraction, morphological studies using scanning electron microscopy (SEM) and transmission electron microscopy (TEM), optical studies using UV-VIS spectroscopy to measure band gap (eV) and chronoamperometry was applied to measure photo response of samples. SEM and TEM studies revealed cubic particles with size varying from 350 nm to 400 nm. XRD studies confirms hematite structure for V-doped and undoped alpha - Fe2O3 samples. Optical studies show a variation of band gap from 1.89 eV similar to 2.09 eV. Chronoamperometry studies revealed that 3%V-doped samples displayed 16 times higher PEC activity with respect to undoped alpha - Fe(2)O(3)film. The higher current density can be attributed to band gap narrowing and increased donor density. Result provided in this work can provide an imperative guideline for the design of efficient photocatalysis application using alpha - Fe2O3.