Fabrication of coral-like Cu2O nanoelectrode for solar hydrogen generation

The direct-grown and coral-like p-type Cu2O nanostructural film on copper foil is successfully fabricated via a facile and cost-effective template route through transformation of Cu(OH)(2) nanowires for photoelectrochemical (PEC) hydrogen generation. The dense Cu2O nanocoral electrode thermally transfers from Cu(OH)(2) nanowires by means of the dehydrate and deoxidization processes under nitrogen atmosphere. Mott-Schottky plot shows the flat-band potential of the coral-like Cu2O nanostructural film to be -0.1 V and a hole concentration of 8.2 x 10(19) cm(-3). Direct band gap of 2.08 eV in Cu2O film is determined via incident photon-to-electron conversion efficiency measurement. Significantly, this Cu2O nanocoral photocathode exhibits remarkable photocurrent of -1.3 mA cm(-2) at a potential of -0.6 V vs Ag/AgCl, corresponding to the solar conversion efficiency of 1.47%. These results demonstrate the great potential of Cu2O nanocoral film in solar hydrogen applications. Crown Copyright (C) 2013 Published by Elsevier B.V. All rights reserved.