Wavelength-induced modifications of thermoelectric properties of laser-textured Bi2Sr2-xBaxCo2O8 ceramics for sustainable energy generation

Özkurt, Pinar ; Madre, M.A. (Universidad de Zaragoza) ; Özkurt, Berdan ; Torres, M.A. (Universidad de Zaragoza) ; Sotelo, A. (Universidad de Zaragoza) ; Rasekh, Sh.

Resumen: Ba-doped Bi2Sr2-xBaxCo2O8 samples have been directionally grown using the Laser Floating Zone technique using two different lasers, leading to significant differences between the samples. Powder XRD patterns revealed that the major phase in all samples is the thermoelectric one, without notable differences with the type of laser. On the other hand, microstructure studies showed significant differences between Nd:YAG and CO2-grown samples. Use of CO2 laser promoted a reduction of secondary phases content and a higher grain alignment. Furthermore, Ba-doping further decreases the secondary phases content and increases grain alignment. The electrical resistivity was affected by the different microstructures, being lower for the CO2-grown samples, reaching the lowest values at 650 °C in 0.125Ba-doped samples, 12.8 mΩ cm, which are among the best reported in the literature. However, S is maintained practically unchanged independently of the laser and composition. As a consequence, PF values mainly depend on the electrical resistivity and, consequently, the highest values at 650 °C, 0.22 mW/K2m, have been achieved in 0.125Ba samples textured with CO2 laser. These values are around the best ones presented in the literature for this material. Additionally these textured materials possess the advantage of avoiding the typical machining processes which are necessary in bulk materials for their integration into thermoelectric modules. These characteristics may enhance the interest on these materials in order to be used in practical devices to help their use to produce affordable, reliable and sustainable energy for all mankind.

Idioma: Inglés

DOI: 10.1016/j.mseb.2025.117985

Año: 2025

Publicado en: Materials Science and Engineering B: Solid-State Materials for Advanced Technology 313 (2025), 117985 [6 pp.]
ISSN: 0921-5107

Financiación: info:eu-repo/grantAgreement/ES/DGA/T54-23R

Tipo y forma: Artículo (PostPrint)

Área (Departamento): Área Expresión Gráfica en Ing. (Dpto. Ingeniería Diseño Fabri.)
Área (Departamento): Área Cienc.Mater. Ingen.Metal. (Dpto. Ciencia Tecnol.Mater.Fl.)