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XPS Study in BiFeO₃ Surface Modified by Argon Etching.

ABSTRACT: This paper reports an XPS surface study of pure phase BiFeO3 thin film produced and later etched by pure argon ions. Analysis of high-resolution spectra from Fe 2p, Bi 4f and 5d, O 1s, and the valence band, exhibited mainly Fe3+ and Bi3+ components, but also reveal Fe2+. High-energy argon etching induces the growth of Fe(0) and Bi(0) and an increment of Fe2+, as expected. The BiFeO3 semiconductor character is preserved despite the oxygen loss, an interesting aspect for the study of the photovoltaic effect through oxygen vacancies in some ceramic films. The metal-oxygen bonds in O 1s spectra are related only to one binding energy contrary to the split from bismuth and iron reported in other works. All these data evidence that the low-pressure argon atmosphere is proved to be efficient to produce pure phase BiFeO3, even after argon etching.

SUBMITTER: Gomez-Iriarte GA

PROVIDER: S-EPMC9227888 | biostudies-literature | 2022 Jun

REPOSITORIES: biostudies-literature

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XPS Study in BiFeO3 Surface Modified by Argon Etching.

Gomez-Iriarte Grecia Alejandra GA Pentón-Madrigal Arbelio A de Oliveira Luiz Augusto Sousa LAS Sinnecker João Paulo JP

Materials (Basel, Switzerland) 20220617 12

This paper reports an XPS surface study of pure phase BiFeO3 thin film produced and later etched by pure argon ions. Analysis of high-resolution spectra from Fe 2p, Bi 4f and 5d, O 1s, and the valence band, exhibited mainly Fe3+ and Bi3+ components, but also reveal Fe2+. High-energy argon etching induces the growth of Fe(0) and Bi(0) and an increment of Fe2+, as expected. The BiFeO3 semiconductor character is preserved despite the oxygen loss, an interesting aspect for the study of the photovolt ...[more]

PMID: 35744344

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