Determination of band structure parameters and the quasi-particle gap of CdSe quantum dots by cyclic voltammetry.

Chemphyschem

Department of Chemistry and DST center for Nanoscience, University of Pune, Ganeshkhind, Pune 411007, India.

Published: December 2008

Band structure parameters such as the conduction band edge, the valence band edge and the quasi-particle gap of diffusing CdSe quantum dots (Q-dots) of various sizes were determined using cyclic voltammetry. These parameters are strongly dependent on the size of the Q-dots. The results obtained from voltammetric measurements are compared to spectroscopic and theoretical data. The fit obtained to the reported calculations based on the semi-empirical pseudopotential method (SEPM)-especially in the strong size-confinement region, is the best reported so far, according to our knowledge. For the smallest CdSe Q-dots, the difference between the quasi-particle gap and the optical band gap gives the electron-hole Coulombic interaction energy (J(e1,h1)). Interband states seen in the photoluminescence spectra were verified with cyclic voltammetry measurements.

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http://dx.doi.org/10.1002/cphc.200800482DOI Listing

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