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Manipulation of Optical Transmittance by Ordered-Oxygen-Vacancy in Epitaxial LaBaCo₂O_5.5+? Thin Films.

ABSTRACT: Giant optical transmittance changes of over 300% in wide wavelength range from 500?nm to 2500?nm were observed in LaBaCo₂O_5.5+? thin films annealed in air and ethanol ambient, respectively. The reduction process induces high density of ordered oxygen vacancies and the formation of LaBaCo₂O_5.5 (??=?0) structure evidenced by aberration-corrected transmission electron microscopy. Moreover, the first-principles calculations reveal the origin and mechanism of optical transmittance enhancement in LaBaCo₂O_5.5 (??=?0), which exhibits quite different energy band structure compared to that of LaBaCo₂O₆ (??=?0.5). The discrepancy of energy band structure was thought to be the direct reason for the enhancement of optical transmission in reducing ambient. Hence, LaBaCo₂O_5.5+? thin films show great prospect for applications on optical gas sensors in reducing/oxidizing atmosphere.

SUBMITTER: Cheng S

PROVIDER: S-EPMC5120332 | biostudies-literature | 2016 Nov

REPOSITORIES: biostudies-literature

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Manipulation of Optical Transmittance by Ordered-Oxygen-Vacancy in Epitaxial LaBaCo2O5.5+δ Thin Films.

Cheng Sheng S Lu Jiangbo J Han Dong D Liu Ming M Lu Xiaoli X Ma Chunrui C Zhang Shengbai S Chen Chonglin C

Scientific reports 20161123

Giant optical transmittance changes of over 300% in wide wavelength range from 500 nm to 2500 nm were observed in LaBaCo2O5.5+δ thin films annealed in air and ethanol ambient, respectively. The reduction process induces high density of ordered oxygen vacancies and the formation of LaBaCo2O5.5 (δ = 0) structure evidenced by aberration-corrected transmission electron microscopy. Moreover, the first-principles calculations reveal the origin and mechanism ...[more]

PMID: 27876830

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