Charge regulation at semiconductor-electrolyte interfaces

Mark E Fleharty; Frank van Swol; Dimiter N Petsev

doi:10.1016/j.jcis.2014.12.058

Charge regulation at semiconductor-electrolyte interfaces

J Colloid Interface Sci. 2015 Jul 1:449:409-15. doi: 10.1016/j.jcis.2014.12.058. Epub 2014 Dec 29.

Authors

Mark E Fleharty¹, Frank van Swol², Dimiter N Petsev¹

Affiliations

¹ Department of Chemical and Biological Engineering, University of New Mexico, Albuquerque, NM 87131, United States.
² Department of Chemical and Biological Engineering, University of New Mexico, Albuquerque, NM 87131, United States; Sandia National Laboratories, P.O. Box 5800, Albuquerque, NM 87185, United States.

PMID: 25595623
DOI: 10.1016/j.jcis.2014.12.058

Abstract

The interface between a semiconductor material and an electrolyte solution has interesting and complex electrostatic properties. Its behavior will depend on the density of mobile charge carriers that are present in both phases as well as on the surface chemistry at the interface through local charge regulation. The latter is driven by chemical equilibria involving the immobile surface groups and the potential determining ions in the electrolyte solution. All these lead to an electrostatic potential distribution that propagate such that the electrolyte and the semiconductor are dependent on each other. Hence, any variation in the charge density in one phase will lead to a response in the other. This has significant implications on the physical properties of single semiconductor-electrolyte interfaces and on the electrostatic interactions between semiconductor particles suspended in electrolyte solutions. The present paper expands on our previous publication (Fleharty et al., 2014) and offers new results on the electrostatics of single semiconductor interfaces as well as on the interaction of charged semiconductor colloids suspended in electrolyte solution.

Keywords: Boltzmann distribution; Charge regulation; Electric double layer; Fermi–Dirac distribution; Particle interactions; Semiconductor colloids.