Manipulating semiconductor colloidal stability through doping.
The interface between a doped semiconductor material and electrolyte solution is of considerable fundamental interest, and is relevant to systems of practical importance. Both adjacent domains contain mobile charges, which respond to potential variations. This is exploited to design electronic and optoelectronic sensors, and other enabling semiconductor colloidal materials. We show that the charge mobility in both phases leads to a new type of interaction between semiconductor colloids suspended in aqueous electrolyte solutions. This interaction is due to the electrostatic response of the semiconductor interior to disturbances in the external field upon the approach of two particles. The electrostatic repulsion between two charged colloids is reduced from the one governed by the charged groups present at the particles surfaces. This type of interaction is unique to semiconductor particles and may have a substantial effect on the suspension dynamics and stability.
Nanoscience and Microsystems Program, University of New Mexico, Albuquerque, New Mexico 87131, USA and Department of Chemical and Biological Engineering, University of New Mexico, Albuquerque, New Mexico 87131, USA.
Mark E
ME
Fleharty
Department of Chemical and Biological Engineering, University of New Mexico, Albuquerque, New Mexico 87131, USA and Sandia National Laboratories, Albuquerque, New Mexico 87185, USA.
Frank
F
van Swol
Department of Chemical and Biological Engineering, University of New Mexico, Albuquerque, New Mexico 87131, USA.
Dimiter N
DN
Petsev
D003102:Colloids / Q000737:chemistry*; D004573:Electrolytes / Q000737:chemistry; D007700:Kinetics; D008956:Models, Chemical; D012666:Semiconductors; D012996:Solutions; D055672:Static Electricity; D013535:Suspensions
D003102:Colloids; D004573:Electrolytes; D012996:Solutions; D013535:Suspensions