Nano Porous Hematite for Solar Hydrogen Production

Nanostructured Zr-doped alpha-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 alpha-Fe2O3 was identified as best performing electrode in PEC cell, showing photocurrent density of 754 mu A/cm(2) at external bias 0.6 V/SCE and 132 mu A/cm(2) under no bias condition. Onset potential of photocurrent exhibited by this sample was -0.32V/SCE, which is a negative shift of approx. 0.9 V to 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 cm(2) size was 0.6 mLh(-1) at 0.6 V/SCE for 1.0% Zr doped alpha-Fe2O3. (C) 2012 The Electrochemical Society. [DOI: 10.1149/2.016208jes] All rights reserved.