Electronic transport of n-type CdSe quantum dot films:: Effect of film treatment

Solid films of CdSe colloidal quantum dots are conductive when reduced by electrochemistry. The dark conductivity and the photoconductivity of these n-type CdSe nanocrystalline solids have been investigated as a function of film treatment. When the films are treated with NaOH, a carrier mobility of similar to 10(-2) cm(2)/V s and a charging/discharging time of similar to 10 ms are obtained. Under an excitation intensity of similar to 0.75 mW/cm(2), a significant photoconductivity of similar to 10(-3) S cm(-1) has been observed. The high mobility allowed demonstrating the operation of a field effect transistor. (c) 2006 American Institute of Physics.