Effect of Cu incorporation on morphology and optical band gap properties of nano-porous lithium magneso-silicate (LMS) thin films

Abstract

A high bandgap semiconductor of Cu doped LMS (Cu-LMS) thin films incorporation in nano-porous lithium magneso-silicate (LMS) thin films as in the formula (10 Li2O: 15 MgO: (75-x) SiO2: (x = 0, 2, 5 and 8) Cu) has been successfully prepared by a facile acidic sol-gel method, spin-coating on glass substrate and then calcined at 450 °C for 5h in air. The x-ray diffraction (XRD) pattern indicated the formation of nanocrystalline anorthic phase for pure (LMS) and Cu doped (Cu-LMS). The surface morphological analysis through the scanning electron microscopy (SEM) approved the formation of nano-size (LMS) with good periodicity and great adherence. The optical measurements revealed an increase in both the refractive index values and the band gap of the nano-porous LMS with increasing Cu content. These results suggest that nano-porous Cu-LMS films can be a good candidate for various optical applications such as sensors, waveguide, and solar cells.