Open AccessMn-doped GaN as photoelectrodes for the photoelectrolysis of water under visible light
Author(s) -
Shu Yen Liu,
Jinn-Kong Sheu,
Yu Chuan Lin,
Shang Ju Tu,
Fenglan Huang,
M. L. Lee,
WeiChi Lai
Publication year - 2012
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.20.00a678
Subject(s) - photoelectrolysis , materials science , visible spectrum , photocurrent , optoelectronics , water splitting , doping , absorption (acoustics) , band gap , optics , electrode , photocatalysis , electrolysis , electrolyte , chemistry , composite material , catalysis , biochemistry , physics
Hydrogen generation through direct photoelectrolysis of water was studied using photoelectrochemical (PEC) cells made of Mn-doped GaN photoelectrodes. In addition to its absorption of the ultraviolet spectrum, Mn-doped GaN photoelectrodes could absorb photons in the visible spectrum. The photocurrents measured from PEC cells made of Mn-doped GaN were at least one order higher than those measured from PEC cells made of undoped GaN-working electrodes. Under the visible light illumination and a bias voltage below 1.2 V, the Mn-doped GaN photoelectrodes could drive the water splitting reaction for hydrogen generation. However, hydrogen generation could not be achieved under the same condition wherein undoped GaN photoelectrodes were used. According to the results of the spectral responses and transmission spectra obtained from the experimental photoelectrodes, the enhanced photocurrent in the Mn-doped GaN photoelectrodes, compared with the undoped GaN photoelectrodes, was attributable to the Mn-related intermediate band within the band gap of GaN that resulted in further photon absorption.