Ba-DOPED ZnO MATERIALS: A DFT SIMULATION TO INVESTIGATE THE DOPING EFFECT ON FERROELECTRICITY

Abstract

publicado na web em 18/02/2015ZnO is a semiconductor material largely employed in the development of several electronic and optical devices due to its unique electronic, optical, piezo-, ferroelectric and structural properties. This study evaluates the properties of Ba-doped wurtzite-ZnO using quantum mechanical simulations based on the Density Functional Theory (DFT) allied to hybrid functional B3LYP. The Badoping caused increase in lattice parameters and slight distortions at the unit cell angle in a wurtzite structure. In addition, the doping process presented decrease in the band-gap (E g ) at low percentages suggesting band-gap engineering. For low doping amounts, the wavelength characteristic was observed in the visible range; whereas, for middle and high doping amounts, the wavelength belongs to the Ultraviolet range. The Ba atoms also influence the ferroelectric property, which is improved linearly with the doping amount, except for doping at 100% or wurtzite-BaO. The ferroelectric results indicate the ZnO:Ba is an strong option to replace perovskite materials in ferroelectric and flash-type memory devices.

Adsorption Behavior of Congo Red onto Barium-Doped ZnO Nanoparticles: Correlation between Experimental Results and DFT Calculations

“…The conducting bands are dominated by Ba 2+ orbitals, while the ZnO orbitals rule the valence bond. The determined band gap is 4 eV, in accordance with preceding studies, indicating an increase in the band gap by Ba doping. , …”

“…The determined band gap is 4 eV, in accordance with preceding studies, indicating an increase in the band gap by Ba doping. 68,69 ■ CONCLUSIONS In this study, ZBO2 NPs synthesized by the co-precipitation process show a great CR adsorption from polluted wastewater. The nanomaterials were characterized by XRD, BET, and SEM.…”

Vibrational, Electronic and Structural Study of Sprayed ZnO Thin Film Based on the IR-Raman Spectra and DFT Calculations

“…The interest of ZnO resides especially in its wide direct band gap (3.4 eV), high n-type conductivity, high thermal conductivity and its large exciton binding (60 meV) [5]. Nevertheless, during the design, the control of structural defects as well as surface and interfacial structures is essential for optimizing the device performance [6]. In addition, it is noted that the growth conditions affect the band gap which is a key parameter in the design of optoelectronic devices.…”