Physics

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Author: search.filters.author.Tomkiewicz MHas files: No

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    Electrolyte Electroreflectance Study of CdIn2Se4 Liquid Junction Solar cells
    (American Physical Soc. Meeting, Los Angeles,USA, 1983) Tomkiewicz M; Siripala W
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    The Interrelation Between the Potential Distribution and the Dark Charge Transfer Across n-TiO2 - Aqueous Electrolyte Interface
    (Symposia on Photoelectrochemical Process and Measurements Techniques for Photoelectrochemical Solar Cells, 1981) Tomkiewicz M; Siripala W
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    Characterization of Surface States at a Semiconductor Electrolyte Interface by Electroreflectance Spectroscopy
    (Journal De Physique, 1983) Tomkiewicz M; Siripala W
    Supra bandgap and subband gap Electrolyte Electroreflectance is being used to characterize surface states at semiconductor liquid interfaces. The surface states can manifest themselves either through direct optical transitions as in the case of n - TiO2 - aqueous electrolyte interface or through their effect on the response of the Fermi level to small changes in the electrode potential as in the case of single crystal CdIn2Se4 in polysulfide solutions.
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    Surface Recombination at n-TiO2 Electrodes in Photoelectrolytic Solar Cells
    (Journal of Electrochemical Society, 1983) Siripala W; Tomkiewicz M
    The photocurrent?potential behavior of photoelectrodes in liquid junction configuration is investigated. The Gartner model is modified to include the surface recombination. Impedance and photocurrent?potential measurements reveal the presence of a high density of surface states at the interface, covering more than half a monolayer. A total of four parameters are used to characterize the surface states. Two of these parameters appear in the expression for both the quantum efficiency?potential dependence and the expression for the capacitance due to these states. The other two parameters appear separately in conjunction with each experiment. The model is tested by perturbating the steady state of the system by strong background illumination which induces higher injection rate of carriers. The effect of the background illumination is interpreted as the change in the equilibrium distribution of the surface states which will result in the increase in surface recombination of photocarriers.
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    Direct Observation of Surface States at the TiO2 Electrolyte Interface
    (Journal of Electrochemical Society, 1981) Siripala W; Tomkiewicz M
    Relaxation Spectrum Analysis was suggested as a general technique for mearsurements of charge accumulation modes and their corresponding relaxation times at the space charge layer of a semiconductor with strong emphasis on semiconductor liquid junction interfaces. Among all the reported results(2-4),none was, as yet, confirmed by an independent technique.