Characterization of copper indium ditelluride/electrolyte interface utilizing electrochemical impedance spectroscopy
Abbreviated Journal Title
Appl. Surf. Sci.
copper indium telluride; semiconductor; impedance; flat-band; surface; chemistry; FILM SOLAR-CELLS; PHOTOLUMINESCENCE SPECTRA; SEMICONDUCTOR ELECTRODES; SINGLE-CRYSTALS; PASSIVE FILM; CUINTE2; DEPENDENCE; FREQUENCY; STEEL; Chemistry, Physical; Materials Science, Coatings & Films; Physics, ; Applied; Physics, Condensed Matter
Copper indium telluride (CIT) is a promising semiconductor material for use in thin film solar cells, especially photoelectrochemical solar cells (PESC). Impedance measurements were used to evaluate the relative band edge positions of polycrystalline n-CuInTe2 electrodes in various aqueous electrolytes, by measuring the extrapolated flat-band potentials, V-fb.By varying applied dc potential, frequency and pH of the electrolyte, the semiconductor-electrolyte interfaces are studied through capacitance measurements and Mott-Schottky analysis. The flat-band potential and carrier concentrations were determined from the Mott-Schottky plots. It was found that V-fb could be shifted depending on the pH of the electrolyte, while it is independent of the testing frequency. The changes in V-fb with pH could be due to surface states and other modifications through etching and polishing. The surface carrier concentrations were found to increase with pH. The different surface chemistry studied by X-ray photoelectron spectroscopy might account for this change. (C) 2004 Elsevier B.V. All rights reserved.
Applied Surface Science
"Characterization of copper indium ditelluride/electrolyte interface utilizing electrochemical impedance spectroscopy" (2005). Faculty Bibliography 2000s. 5744.