Carbon coated Cu2O nanowires for photo-electrochemical water splitting with enhanced activity

Herein, we report on Cu2O nanowire photocathode covered with amorphous carbon thin layer by a simple and effective anodization method for photoelectrochemical (PEC) water splitting hydrogen production. The coating of carbon thin layer increases the photo-electrochemical performance of Cu2O nanowires, achieving a photocurrent density of up to 2.7 mA cm(-2) at 0 V (vs. RHE) with a maximum photon to current conversion efficiency of 0.28% at 0.21 V (vs. RHE) under standard testing conditions. The nanocomposite electrode retains 61.3% of its photo-activity after 1000 s irradiation, which is higher than that of bare Cu2O (18.5%). The detailed investigation results reveal that the augmented photocurrent as well as the enhanced stability could be contributed to the acceleration of electrochemical charge transfer at the electrode/electrolyte interface and the reduced rate of photo-corrosion. (C) 2015 Elsevier B.V. All rights reserved.