Nano Porous Hematite for Solar Hydrogen Production

Abstract

Nanostructured Zr-doped α-Fe2O3 thin films were successfully synthesized and studied for photoelectrochemical (PEC) generation of hydrogen through splitting of water. PEC data were analyzed with the supporting information obtained by Scanning electron microscopy, X-ray diffraction, Raman spectroscopy, UV-Vis optical spectroscopy, and X-ray photoelectron spectroscopy. Donor density, grain size and porosity of the films were observed to be highly affected by Zr doping, which in turn resulted in the sample with enhanced photoresponse. 1.0% Zr doped α-Fe2O3 was identified as best performing electrode in PEC cell, showing photocurrent density of 754 μA/cm2 at external bias 0.6 V/SCE and 132 μA/cm2 under no bias condition. Onset potential of photocurrent exhibited by this sample was - 0.32V/SCE, which is a negative shift of approx. 0.9Vto the value exhibited by undoped samples. STH efficiency for best performing electrode was 0.46% at 0.6V/SCE. The measured rate of hydrogen production with an electrode of 1 cm2 size was 0.6 mLh-1 at 0.6 V/SCE for 1.0% Zr doped α-Fe2O3. © 2012, The Electrochemical Society, Inc. All rights reserved.