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(Referência obtida automaticamente do Web of Science, por meio da informação sobre o financiamento pela FAPESP e o número do processo correspondente, incluída na publicação pelos autores.)

Bandgap narrowing of Ba0.92Na0.04Bi0.04TiO3 ferroelectric ceramics by transition metals doping for photovoltaic applications

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Autor(es):
Alkathy, Mahmoud S. [1] ; Lente, Manuel H. [2] ; Eiras, J. A. [1]
Número total de Autores: 3
Afiliação do(s) autor(es):
[1] Univ Fed Sao Carlos, CCET, Phys Dept, BR-13565905 Sao Carlos, SP - Brazil
[2] Univ Fed Sao Paulo, Inst Ciencia & Tecnol, BR-12231280 Sao Jose Dos Campos, SP - Brazil
Número total de Afiliações: 2
Tipo de documento: Artigo Científico
Fonte: Materials Chemistry and Physics; v. 257, JAN 1 2021.
Citações Web of Science: 4
Resumo

A wide bandgap is one of the greatest issues that restrain the photoelectric application of classical ferroelectric oxides in the visible spectrum. Typical approaches to reduce their bandgap, as well as to tune other physical properties (dielectric, piezoelectric ...), is to use specific dopants. This work reports the variation by doping of the structural and optical bandgap properties of the Ba0.92Bi0.04Na0.04Ti0.96M0.04O3 (BNBT-M); (M = Ni, Fe, Co) ceramics. Structural refinement shows that all samples are crystallized with a tetragonal phase with a P4mm space group. Detailed analysis of the bond lengths, bond angles, octahedral distortions demonstrates the cooperative effect induced by the Co, Fe, and Ni doping. UV-Vis absorption spectra showed a decrease in the bandgap and increased absorption for longer wavelengths, induced by transitions metal (TM) ions doping. The bandgap narrowing is attributed to the development of new M - O bonds and states in the electronic structure, as the TM ions are incorporated on the Ti site, with simultaneous oxygen vacancies creation. The formation of oxygen vacancies via metal ions doping in BNBT was proven by ESR study. The present investigation can provide useful insight into the understanding and ferroelectrics bandgap tuning for visible-light photovoltaic applications. (AU)

Processo FAPESP: 17/13769-1 - Materiais multiferróicos e ferroelétricos para conversores de energia: síntese, propriedades, fenomenologia e aplicações
Beneficiário:José Antonio Eiras
Modalidade de apoio: Auxílio à Pesquisa - Temático
Processo FAPESP: 19/03110-8 - Síntese e caracterização fotovoltaica de filmes finos à base de perovskitas ferroelétricas e multiferróicas para aplicação em células solares
Beneficiário:Mahmoud Saleh Mohammed Alkathy
Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado