Charge transfer in Pr-Doped cerium oxide: Experimental and theoretical investigations

Autor(es):Mostrar menos -

de Oliveira, Regiane Cristina ^{[1, 2, 3]} ; Cabral, Luis ^[4] ; Cabral, Ana Cristina ^[5] ; Almeida, Priscila Barros ^[6] ; Tibaldi, Nicolas ^{[7, 8]} ; Sambrano, Julio Ricardo ^[2] ; Simoes, Alexandre Zirpoli ^{[1, 9]} ; Macchi, Carlos Eugenio ^[10] ; Moura, Francisco ^[5] ; Marques, Gilmar Eugenio ^[4] ; Ponce, Miguel Adolfo ^{[7, 8]} ; Longo, Elson ^[6]

Afiliação do(s) autor(es)

^[1] Sao Paulo State Univ UNESP, Fac Engn Guaratingueta, Guaratingueta, SP - Brazil

^[2] Sao Paulo State Univ, UNESP, Modeling & Mol Simulat Grp, Bauru, SP - Brazil

^[3] Sao Paulo State Univ, UNESP, Modeling & Mol Simulat Grp, Baum, SP - Brazil

^[4] Univ Fed Sao Carlos, Dept Phys, BR-13565905 Sao Carlos, SP - Brazil

^[5] Univ Fed Itajuba, Lab Interdisciplinar Mat Avancados, Unifei Campus, Itabira, MG - Brazil

^[6] Fed Univ Sao Carlos UFSCar, LIEC, CDMF, Chem Dept, POB 676, BR-13565905 Sao Carlos, SP - Brazil

^[7] Univ Mar del Plata, Inst Mat Sci & Technol INTEMA, Juan B Justo 4302, B7608FDQ, RA-4302 Mar Del Plata - Argentina

^[8] Natl Res Council CONICET, Juan B Justo 4302, B7608FDQ, RA-4302 Mar Del Plata - Argentina

^[9] de Oliveira, Regiane Cristina, Sao Paulo State Univ, UNESP, Modeling \& Mol Simulat Grp, Baum, SP, Brazil.de Oliveira, Regiane Cristina, Sao Paulo State Univ UNESP, Fac Engn Guaratingueta, Guaratingueta, SP - Brazil

^[10] UE CIFICEN CONICET Consejo Nacl Invest Cient & Te, Inst Fis Mat Tandil, Pinto 399, B7000GHG, Tandil - Argentina

• Tipo de documento: Artigo Científico
• Fonte: Materials Chemistry and Physics; v. 249, JUL 15 2020.
• Citações Web of Science: 0

Resumo

In this study was synthesized cerium oxide (CeO2) doped with praseodymium (Pr) using a microwave-assisted hydrothermal method. The positions of the vacancies with respect to Ce3+/Ce4+ and the vacancy-like defects surrounded by the electronic density of Pr atoms were determined through photoluminescence (PL) measurements, positron annihilation lifetime spectroscopy, and density functional theory (DFT). Distinct PL responses were observed for Pr-doped CeO2 indicating that oxygen vacancies contribute to the formation of deep energy levels in the forbidden region, thus facilitating charge transfer. The interplay between the experimental measurements and computational simulations at the microscopic level based on DFT revealed the charge rearrangement in oxygen-deficient CeO2:Pr systems. These results indicate that oxygen vacancies and electrons at the 4f states contribute to electrical conduction, thereby demonstrating that Pr-doped CeO2 acts as an n-type semiconductor. (AU)

• Processo FAPESP: 19/08928-9 - Modelagem e Simulações da Funcionalização de Nanotubos Porosos Inorgânicos
• Beneficiário: Julio Ricardo Sambrano
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 18/20729-9 - Formação de Nanopartículas de Prata por Irradiação a Laser: Uma Investigação ab initio
• Beneficiário: Luis Antônio Cabral
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado
• Processo FAPESP: 08/57872-1 - Instituto Nacional de Ciências dos Materiais em Nanotecnologia
• Beneficiário: Elson Longo da Silva
• Modalidade de apoio: Auxílio à Pesquisa - Temático
• Processo FAPESP: 13/07296-2 - CDMF - Centro de Desenvolvimento de Materiais Funcionais
• Beneficiário: Elson Longo da Silva
• Modalidade de apoio: Auxílio à Pesquisa - Centros de Pesquisa, Inovação e Difusão - CEPIDs