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Defect Engineering Enhances the Charge Separation of CeO₂ Nanorods toward Photocatalytic Methyl Blue Oxidation.

ABSTRACT: Defect-rich photocatalytic materials with excellent charge transfer properties are very popular. Herein, Sm-doped CeO₂ nanorods were annealed in a N₂ atmosphere to obtain the defective Sm-doped CeO₂ photocatalysts (Vo-Sm-CeO₂). The morphology and structure of Vo-Sm-CeO₂ were systematically characterized. The Vo-Sm-CeO₂ nanorods demonstrated an excellent photodegradation performance of methyl blue under visible light irradiation compared to CeO₂ nanorods and Sm-CeO₂. Reactive oxygen species including OH, ·O₂^-, and h⁺ were confirmed to play a pivotal role in the removal of pollutants via electron spin resonance spectroscopy. Doping Sm enhances the conductivity of CeO₂ nanorods, benefiting photogenerated electrons being removed from the surface reactive sites, resulting in the superior performance.

SUBMITTER: Yang J

PROVIDER: S-EPMC7700514 | biostudies-literature | 2020 Nov

REPOSITORIES: biostudies-literature

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Defect Engineering Enhances the Charge Separation of CeO2 Nanorods toward Photocatalytic Methyl Blue Oxidation.

Yang Jindong J Xie Ning N Zhang Jingnan J Fan Wenjie W Huang Yongchao Y Tong Yexiang Y

Nanomaterials (Basel, Switzerland) 20201121 11

Defect-rich photocatalytic materials with excellent charge transfer properties are very popular. Herein, Sm-doped CeO2 nanorods were annealed in a N2 atmosphere to obtain the defective Sm-doped CeO2 photocatalysts (Vo-Sm-CeO2). The morphology and structure of Vo-Sm-CeO2 were systematically characterized. The Vo-Sm-CeO2 nanorods demonstrated an excellent photodegradation performance of methyl blue under visible light irradiation co ...[more]

PMID: 33233419

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