A DFT study of copper-oxide clusters embedded in dry and water-immersed siliceous mordenite

Abstract

A theoretical study of different composite materials obtained by hosting a variety of copper-oxide clusters within the main channel of mordenite was carried out based on periodic density functional theory calculations. Results show that in mordenite framework (siliceous or aluminized) oxygen atoms are responsible for electronic conduction, while in composites, this is modified by the presence of copper-oxide clusters which produce a reduction of the energy band gap as an effect of introducing additional Cu-d and O-p orbital electronic levels. We found that the tuning of distinct orbitals involved in composites’ electronic conduction depends upon the local environment surrounding copper-oxide clusters. The continuum medium approach was employed to evaluate the effect of immersing a composite in water on the electronic properties, and a comparison with the dry case counterpart is presented.