The effects of oxygen adsorption on the conductivity and carrier transport mechanisms in CdS nanowires were established through variable temperature electrical transport and photoconductivity measurements. n -type CdS nanowires were found to be significantly less conductive in the ambient air than in the vacuum due to electron depletion induced by adsorbed oxygen. The current-voltage characteristics of depleted nanowires exhibited a power law behavior consistent with space-charge-limited conduction in the presence of traps. Analysis of the voltage and temperature dependencies of the space-charge-limited current showed that the nanowire surface traps are exponentially distributed in energy with a characteristic depth of ∼0.28±0.04 eV.
ASJC Scopus subject areas
- Physics and Astronomy (miscellaneous)