Photoinduced charge transfer studies of type-II core-shell ZnTe-ZnSe quantum dots

摘要

In this communication, we discuss the photoinduced charge transfer between type-II ZnTe-ZnSe core-shell quantum dots and a molecular adsorbate methyl viologen. The oleic acid-capped core-shell nanostructures were synthesized using organometallic high-temperature route and were characterized using UV-visible absorption spectroscopy, photoluminescence spectroscopy, X-ray diffraction, high-resolution transmission electron microscopy, selected area electron diffraction, inductive coupled plasma optical emission spectroscopy, energy dispersive X-ray spectroscopy and X-ray photoelectron spectroscopy. The charge transfer behaviour of the core-shell quantum dots in the presence of methyl viologen was investigated by monitoring variations in photoluminescence and life time using steady-state and time-resolved techniques, and the results indicated static processes in the charge transfer interactions. The charge transfer capability of a core-shell system is extremely important while considering it in photovoltaic applications.