The photoluminescence (PL) properties of TOPO capped CdSe quantum dots (Q-CdSe) monolayers deposited on indium tin oxide (ITO) substrates and incorporated into an electrochemical cell have been studied. In particular, the effect of electrochemical charge injection by combining the electrochemical set-up with fluorescence spectroscopy has been investigated. It was observed that when positive potentials are applied to the film in electrolyte solution, the PL is irreversibly quenched. However, the PL quenching observed after applying negative potentials to the substrate was reversible. In addition, the changes in the PL exhibit characteristic profiles at particular applied potentials. Voltammetric measurements were performed to further understand the possible origins of the specific PL changes as a function of applied potential. The results have the prospect to prove helpful in explaining the phenomenon of PL intermittency or blinking in semiconductor quantum dots.
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