Electrical assessment of brownmillerite-type calcium ferrite materials obtained by proteic sol-gel route and by solid-state reaction using mollusk shells
| Autor: | Allan J.M. Araújo, João P.F. Grilo, Chrystian G.M. Lima, Gabriel Constantinescu, Andrei V. Kovalevsky, Rafael A. Raimundo, Rinaldo M. Silva, Daniel A. Macedo |
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| Jazyk: | angličtina |
| Rok vydání: | 2021 |
| Předmět: |
food.ingredient
Materials science Solid-state chemistry.chemical_element 02 engineering and technology engineering.material Calcium 010402 general chemistry 01 natural sciences Gelatin Inorganic Chemistry food Proteic sol-gel synthesis Materials Chemistry Brownmillerite Ceramic Physical and Theoretical Chemistry Single phase Sol-gel Solid-state reaction Mollusk shells Calcium ferrite 021001 nanoscience & nanotechnology Condensed Matter Physics 0104 chemical sciences Electronic Optical and Magnetic Materials chemistry Chemical engineering visual_art Ceramics and Composites engineering visual_art.visual_art_medium Electrical properties Ca2Fe2O5 0210 nano-technology |
| Zdroj: | Repositório Científico de Acesso Aberto de Portugal Repositório Científico de Acesso Aberto de Portugal (RCAAP) instacron:RCAAP |
| Popis: | In this work, brownmillerite-type calcium ferrite (Ca2Fe2O5) ceramics were prepared by two distinct routes, namely by a proteic sol-gel synthesis using commercial flavorless gelatin, and by a solid-state reaction method using mollusk shells. XRD analyses revealed single phase brownmillerite-type calcium ferrites in both cases. SEM-EDS analysis of sintered Ca2Fe2O5 ceramics revealed larger grain sizes for the samples prepared via the solid-state reaction. All samples possessed a p-type conduction mechanism, with the largest power factor of ~2 μW m-1 K−2 at 450 °C observed for the samples obtained via the solid state reaction. The charge transport mechanism was found to depend on the preparation route. The obtained results demonstrated that the proposed synthesis routes can be successfully employed for the preparation of single-phase brownmillerite-type materials. |
| Databáze: | OpenAIRE |
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