Hydrogen evolution at a Pt-modified InP photoelectrode: Improvement of current-voltage characteristics by HCl etching

Journal Article · Thu Jan 24 00:00:00 EST 1991 · Journal of Physical Chemistry; (USA)

DOI:https://doi.org/10.1021/j100155a062· OSTI ID:5880269

Kobayashi, Hikaru; Mizuno, Fumiaki; Nakato, Yoshihiro; Tsubomura, Hiroshi ^[1]

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1. Osaka Univ. (Japan)

Hydrogen photoevolution at p-InP electrodes coated with platinum and palladium has been studied. Efficient and stable solar to chemical energy conversion has been achieved after etching the electrodes with concentrated HCl. The current-voltage (I-V) behavior of the as-prepared electrode covered with a continuous Pt layer is poor, due probably to the presence of defect states in InP. The photocurrent density of this electrode decreases with time under illumination, presumably due to an increase in the defect density. After etching of the electrode with concentrated HCl, the barrier height is increased to 1.0 V, and the I-V characteristics are improved remarkably, showing no degradation under illumination. SEM, XPS, and AES analyses show that the concentrated HCl solution dissolves the InP substrate in the InP/Pt interfacial region, and simultaneously part of the Pt is removed from the InP surface. The I-V characteristics of the Pt-deposited electrodes are unaffected by hydrogen or nitrogen bubbling and the reason is discussed.

• OSTI ID: 5880269
• Journal Information: Journal of Physical Chemistry; (USA), Vol. 95:2; ISSN 0022-3654
• Country of Publication: United States
• Language: English

Related Subjects

08 HYDROGEN
14 SOLAR ENERGY
HYDROGEN PRODUCTION
PHOTOELECTROLYSIS
AUGER ELECTRON SPECTROSCOPY
ELECTRIC CONDUCTIVITY
HYDROCHLORIC ACID
INDIUM PHOSPHIDES
PHOTOELECTRON SPECTROSCOPY
SCANNING ELECTRON MICROSCOPY
SOLAR ENERGY CONVERSION
CONVERSION
ELECTRICAL PROPERTIES
ELECTROLYSIS
ELECTRON MICROSCOPY
ELECTRON SPECTROSCOPY
ENERGY CONVERSION
HYDROGEN COMPOUNDS
INDIUM COMPOUNDS
INORGANIC ACIDS
LYSIS
MICROSCOPY
PHOSPHIDES
PHOSPHORUS COMPOUNDS
PHYSICAL PROPERTIES
PNICTIDES
SPECTROSCOPY
080106* - Hydrogen- Production- Biosynthesis & Photochemical Processes
140505 - Solar Energy Conversion- Photochemical
Photobiological
& Thermochemical Conversion- (1980-)