M. Amlouk

Structural and Optothermal Properties of Iron Ditelluride Layered Structures in the Framework of the Lattice Compatibility Theory

This study concerns structural and optothermal properties of iron ditelluride layered structures which were fabricated via a low-cost protocol. The main precursors were FeCl3 · 6H2O and Fe2O3. After a heat treatment within a tellurium-rich medium at various temperatures (470°C, 500°C, and 530°C) during 24 h, classical analyses have been applied to the iron ditelluride layered structures. A good crystalline state with a preferential orientation of the crystallites along (111) direction has been recorded. Moreover, additional opto-thermal investigation and analyses within the framework of the Lattice Compatibility Theory gave plausible explanation for prompt temperature-dependent incorporation of tellurium element inside hematite elaborated matrices.

Effect of europium content on physical properties of In2O3 thin films for sensitivity and optoelectronic applications

In2O3 : Eu thin films were successfully grown by spray pyrolysis. XRD studies showed that the films had In2O3 cubic structure with (004) preferential orientation and best crystal properties at 1.5% Eu doping level. The optical band gap energy decreased with Eu content around 4.1 eV. Urbach energy was of the order of 278 meV, it decreased with Eu content which indicates a decrease in the defects by doping. The dispersion of the refractive index was discussed. Raman spectroscopy showed the band positions corresponding to In2O3 cubic phase with a small shift related to europium incorporation within In2O3 matrix. PL measurements showed a large band which was located at 410 nm and related to the band-to-band transitions and other bands related to impurity levels. Finally, the electric conductivity was investigated depending on the effect of temperature. Activation energy was found to range from 45 to 60 meV for films which were prepared with 1% Eu content.