Chemisorption on semiconductors: The role of quantum corrections on the space charge regions in multiple dimensions

Abstract: The chemisorption of O2 on nanoscale n-doped CdS semiconductors is computed in terms of a Wolkenstein isotherm coupled to the Schrödinger Poisson equation. Present numerical results show the dependence of the chemisorbed charge and the differential capacitance on oxygen partial pressure. A comparison against the classical Poisson-Boltzmann approach shows a higher chemisorbed charge in the quantum model, but a greater differential capacitance in the classical case.

Energy diagram of an n -type doped semiconductor exhibiting an upward band bending at the surface. The subscripts c and v are for the conduction band and the valence band, and the superscripts bulk and surf indi- cate bulk ( x ! À1 ) and surface ( x 1⁄4 0), respectively.

Francesco Ciucci, Carlo de Falco, Marcelo I. Guzman, Sara Lee, Tomonori Honda; Chemisorption on semiconductors: The role of quantum corrections on the space charge regions in multiple dimensions. Appl. Phys. Lett. 30 April 2012; 100 (18): 183106. https://doi.org/10.1063/1.4709483

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