Synthesis And Spectral Characterization Of Lithium Li And Vanadium V Doped BiFeO3 For Photovoltaic Applications

Abstract

ABSTRACT newlineFerroelectric photovoltaic effect is distinct conventional photovoltaic effect observed in semiconductor pn junctions. For FE-PV devices, photocurrent is primarily driven by internal polarization electric field, not by built-in field of a junction. Notably, these devices sometimes exhibit the anomalous photovoltaic effect, where the photovoltage generated along the direction of polarization can exceed bandgap of ferroelectric material. This research focuses on the synthesis, characterization, and optimization of bismuth ferrite-lithium vanadate solid solutions doped with rare earth elements (gadolinium and lanthanum) for enhanced photovoltaic and enhanced multifunctional device applications. newlineBismuth ferrite (BiFeOand#8323;), an environmentally friendly lead-free multiferroic material, demonstrates both ferroelectric and antiferromagnetic properties at room temperature. However, its practical applications are limited by certain constraints including relatively wide band gap and dielectric losses. To address these limitations, this study investigates the formation of solid solutions between bismuth ferrite and lithium vanadate (LiVOand#8323;), subsequently modified through rare earth doping. newlineIn this work we have systematically synthesized and characterized parent BiFeOand#8323;-LiVOand#8323; and two series of compounds: 0.5(Biand#8321;and#8331;and#8339;Gdand#8339;FeOand#8323;) 0.5(LiVOand#8323;) and 0.5(Biand#8321;and#8331;and#8339;Laand#8339;FeOand#8323;) 0.5(LiVOand#8323;) with doping concentrations of x = 0.1, 0.2, and 0.3. All materials were fabricated using high-temperature solid-state reaction methods and comprehensively characterized for structural, morphological, dielectric, electrical, and optical properties. newlineX-ray diffraction analysis confirmed successful formation of pure-phase compounds with a structural transformation from rhombohedral to tetragonal crystal system upon doping. Scanning electron microscopy revealed densely packed grains with uniform distribution and varied morphologies including triangular, rectangular, and spherical particles. Energy dispersive X-ray spectroscopy validated the presence of all constitu