Octahedral distortion and oxygen vacancies induced band-gap narrowing and enhanced visible light absorption of Co/Fe co-doped Bi(3.25)Nd(0.75)Ti(3)O(12)ferroelectrics for photovoltaic applications

Autor(es)

Alkathy, Mahmoud S. ^[1] ; Zabotto, Fabio L. ^[1] ; Lente, Manuel H. ^[2] ; Eiras, J. A. ^[1]

Afiliação do(s) autor(es)

^[1] Univ Fed Sao Carlos, Dept Phys, BR-13565905 Sao Carlos, SP - Brazil

^[2] Univ Fed Sao Paulo, Inst Ciencia & Tecnol, BR-12231280 Sao Jose Dos Campos, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: JOURNAL OF PHYSICS D-APPLIED PHYSICS; v. 53, n. 46 NOV 11 2020.
• Citações Web of Science: 0

Resumo

Reducing bandgap energy in ferroelectric materials has become an important commitment to improve the performance of the photovoltaic solar cell. This study reports the effect of the transition metals Co and Fe ions co-doping on the structure and bandgap of neodymium-modified Bi(4)Ti(3)O(12)based oxide. The quantitative structural analyses by XRD confirms well-crystallized samples with orthorhombic crystal structure based on B2cb space group. Optical properties were measured by a UV-vis spectrometer. The oxygen vacancies presence and the Fe and Co valence states estimation were carried out by electron spin resonance. The incorporation of Co and Fe ions into Bi(3.25)Nd(0.75)Ti(3)O(12)significantly modified the bandgap structure, promoting a red-shift and lower energies absorption which was related to the changes in tilting angles, bond lengths, octahedral distortions and oxygen vacancies formation, still maintaining a ferroelectric spontaneous polarization. To our knowledge, it is a new approach to link quantitively the octahedra distortion to the bandgap decreasing for Aurivillius compounds providing a newly available method of manipulating the bandgap tuning on the ferroelectric oxide's materials. (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