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Energy Express

  • Editor: C. Martijn de Sterke
  • Vol. 19, Iss. S6 — Nov. 7, 2011
  • pp: A1196–A1201

Hydrogen gas generation using n-GaN photoelectrodes with immersed Indium Tin Oxide ohmic contacts

Shu-Yen Liu, Yu-Chuan Lin, Jhao-Cheng Ye, S. J. Tu, F. W. Huang, M. L. Lee, W. C. Lai, and J. K. Sheu  »View Author Affiliations

Optics Express, Vol. 19, Issue S6, pp. A1196-A1201 (2011)

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An n-GaN photoelectrochemical (PEC) cell with immersed finger-type indium tin oxide (ITO) ohmic contacts was demonstrated in the present study to enhance the hydrogen generation rate. The finger-type ITO ohmic contacts were covered with SiO2 layers to prevent the PEC cell from generating leakage current. Using a 1M NaCl electrolyte and external biases, the typical photocurrent density and gas generation rate of the n-GaN working electrodes with ITO finger contacts were found to be higher than those with Cr/Au finger contacts. The enhancement in photocurrent density or gas generation rate can be attributed to the transparent ITO contacts which allowed the introduction of relatively more photons into the GaN layer. No significant corrosion was observed in the ITO layer after the PEC process compared with the Cr/Au finger contacts which were significantly peeled from the GaN layer. These results indicate that the use of n-GaN working electrodes with finger-type ITO ohmic contacts is a promising approach for PEC cells.

© 2011 OSA

OCIS Codes
(310.3840) Thin films : Materials and process characterization
(310.4925) Thin films : Other properties (stress, chemical, etc.)
(310.6845) Thin films : Thin film devices and applications
(310.7005) Thin films : Transparent conductive coatings

ToC Category:

Original Manuscript: August 8, 2011
Revised Manuscript: September 16, 2011
Manuscript Accepted: September 19, 2011
Published: October 3, 2011

Shu-Yen Liu, Yu-Chuan Lin, Jhao-Cheng Ye, S. J. Tu, F. W. Huang, M. L. Lee, W. C. Lai, and J. K. Sheu, "Hydrogen gas generation using n-GaN photoelectrodes with immersed Indium Tin Oxide ohmic contacts," Opt. Express 19, A1196-A1201 (2011)

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