DFT-based computational investigations of structural, mechanical, optoelectronics, and thermoelectric properties of InXF <sub>3</sub> (X = Be and Sr) ternary fluoroperovskites compounds

There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.

Abstract

Wide-band gap semiconductors are very interesting due to their high frequency applications. Perovskite have proved to be most stable structures useful for many applications e.g. solar cells detectors etc The current work is based on the prediction of two new materials (InXF ₃ where X = Be and Sr) for the use of high energy applications. The modelling and simulations were performed through the WIEN2K and BoltzTrap2 packages. The most accurate and precise exchange-correlation of TB-mBJ potential interfaced within WIEN2K is utilized for obtaining better results. The results showed that the selected compounds possess a cubic crystal structure with a space group of Pm-3m (#221). The Goldschmidt’s tolerance factor ( τ) is determined and is found to be 0.96 for InBeF ₃ and 0.92 for InSrF ₃ which indicates the stability of the compounds in cubic phase. The unit cell crystal structural optimization is done to evaluate the ground state lattice parameters. Both the compounds possess a semiconducting nature having an indirect band gap of 3.06 eV for InBeF ₃ from M-X symmetry points while a direct band gap from X-X of 3.98 eV for InSrF ₃ compound. The optical properties are computed and analyzed from the optical dielectric function for both the compounds within the energy range of 0 eV to 40 eV and the results depict that these materials are more sensitive at higher energy range, possess high absorption and optical conductivity in good agreement with electronic band structure. Mechanically these compounds are stable, ductile, anisotropic, and hard to scratch. The thermoelectric properties are evaluated for InXF ₃ (X = Be and Sr) compounds up to a temperature range of 1000 K. This work can open new opportunities for further exploration in this field.

Related collections

Most cited references 31

Record: found
Abstract: not found
Article: not found

A technique for relativistic spin-polarised calculations

D D Koelling, B Harmon (1977)

0 comments Cited 486 times – based on 0 reviews      Review now

Bookmark

Record: found
Abstract: found
Article: not found

High-performance bulk thermoelectrics with all-scale hierarchical architectures.

Kanishka Biswas, Jiaqing He, Ivan Blum … (2012)

With about two-thirds of all used energy being lost as waste heat, there is a compelling need for high-performance thermoelectric materials that can directly and reversibly convert heat to electrical energy. However, the practical realization of thermoelectric materials is limited by their hitherto low figure of merit, ZT, which governs the Carnot efficiency according to the second law of thermodynamics. The recent successful strategy of nanostructuring to reduce thermal conductivity has achieved record-high ZT values in the range 1.5-1.8 at 750-900 kelvin, but still falls short of the generally desired threshold value of 2. Nanostructures in bulk thermoelectrics allow effective phonon scattering of a significant portion of the phonon spectrum, but phonons with long mean free paths remain largely unaffected. Here we show that heat-carrying phonons with long mean free paths can be scattered by controlling and fine-tuning the mesoscale architecture of nanostructured thermoelectric materials. Thus, by considering sources of scattering on all relevant length scales in a hierarchical fashion--from atomic-scale lattice disorder and nanoscale endotaxial precipitates to mesoscale grain boundaries--we achieve the maximum reduction in lattice thermal conductivity and a large enhancement in the thermoelectric performance of PbTe. By taking such a panoscopic approach to the scattering of heat-carrying phonons across integrated length scales, we go beyond nanostructuring and demonstrate a ZT value of ∼2.2 at 915 kelvin in p-type PbTe endotaxially nanostructured with SrTe at a concentration of 4 mole per cent and mesostructured with powder processing and spark plasma sintering. This increase in ZT beyond the threshold of 2 highlights the role of, and need for, multiscale hierarchical architecture in controlling phonon scattering in bulk thermoelectrics, and offers a realistic prospect of the recovery of a significant portion of waste heat.

0 comments Cited 429 times – based on 0 reviews      Review now

Bookmark

Record: found
Abstract: found
Article: not found

New and old concepts in thermoelectric materials.

Joseph Sootsman, Duck-Young Chung, Mercouri Kanatzidis (2009)

Herein we cover the key concepts in the field of thermoelectric materials research, present the current understanding, and show the latest developments. Current research is aimed at increasing the thermoelectric figure of merit (ZT) by maximizing the power factor and/or minimizing the thermal conductivity. Attempts at maximizing the power factor include the development of new materials, optimization of existing materials by doping, and the exploration of nanoscale materials. The minimization of the thermal conductivity can come through solid-solution alloying, use of materials with intrinsically low thermal conductivity, and nanostructuring. Herein we describe the most promising bulk materials with emphasis on results from the last decade. Single-phase bulk materials are discussed in terms of chemistry, crystal structure, physical properties, and optimization of thermoelectric performance. The new opportunities for enhanced performance bulk nanostructured composite materials are examined and a look into the not so distant future is attempted.