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Mst. Irin Naher

Publications and source records attributed to Mst. Irin Naher.

2 recordsLinked to original sources

First-Principles Investigation of the Pressure Dependent Physical Properties of Intermetallic Kagome ZrRe2

We present a density functional theory investigation of the pressure dependent structural, electronic, mechanical, thermophysical, vibrational, and optical properties of the intermetallic Kagome compound ZrRe2. The calculated ground-state structural parameters are in excellent agreement with available experimental results. The estimated structural parameters, elastic constants, and phonon dispersion confirm the structural, chemical, mechanical, and dynamical stability of ZrRe2 up to 25 GPa. The Kagome feature in the material has been identified from the electronic band structure for the first time. ZrRe2 exhibits topological feature at 0 GPa, which vanishes under 25 GPa. Fermi surface (FS) analysis predicts that ZrRe2 could potentially host a charge density wave (CDW) phase. The electronic and optical studies confirmed its metallic nature. The Debye temperature and phonon thermal conductivity are moderate, while the melting point is relatively high. Furthermore, ZrRe2 possesses moderate electron-phonon coupling, which weakens under pressure as the phonon modes harden. Consequently, the superconducting transition temperature decreases with increasing pressure. Most of the properties studied and analyses performed in this paper are novel in nature.

cond-mat.mtrl-sci↗

A facile top-down synthesis of phase pure CuBi2O4 photocathode materials by low-energy sequential ball milling

Kusachiite (copper bismuth oxide) is one of the most promising photocathode materials for high solar-to-hydrogen production efficiency. Here we attempt to synthesize phase pure copper bismuth oxide (CuBi2O4) nanopowders using a facile solid-state reaction technique, subsequently sintered at 750 0C for 4 h in air. These CuBi2O4 (CBO) powders have been further sequentially ball-milled (SBM) up to 25 h to elucidate the milling duration effect on the optical bandgap of the ball-milled CuBi2O4 (SBM-CBO). The X-ray diffractometry (XRD), Raman, X-ray Photoelectron spectroscopy (XPS), and UV-VIS-NIR Diffuse reflection studies suggest that phase pure tetragonal CBO could be grown from raw CuO and Bi2O3 powders. The variations in morphology and chemical composition of CBO with increasing milling hours were examined using field emission scanning electron microscopy (FE-SEM) and Energy Dispersive X-ray (EDX) microanalysis, respectively. The optical bandgap of SBM-CBO powders was measured in the range of approx. 1.70 - 1.85 eV. Photoelectrochemical studies of SBM-CBO slurry atop the screen-printed electrode with aqueous Na2SO4 electrolyte suggest its suitability as photocathode materials for sunlight-driven hydrogen production.

cond-mat.mtrl-sci↗