Electrical transport mechanisms of Neodymium-doped rare-earth semiconductors

Author(s):Show less -

Vaz, Isabela C. F. ; Macchi, Carlos Eugenio ; Somoza, Alberto ; Rocha, Leandro S. R. ; Longo, Elson ; Cabral, Luis ; da Silva, Edison Z. ; Simoes, Alexandre Zirpoli ; Zonta, Giulia ; Malagu, Cesare ; Desimone, P. Mariela ; Ponce, Miguel Adolfo ; Moura, Francisco

• Document type: Journal article
• Source: JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS; v. 33, n. 15, p. 18-pg., 2022-04-26.

Abstract

This study reports the electrical properties of Nd-doped cerium oxide (CeO2) films synthesized by microwave assisted hydrothermal using a two-point probe technique. Positron annihilation lifetime spectroscopy studies evidenced that, as the Nd content rises, a structural disorder occurs. This is caused by an increase in oxygen vacancies surrounded with Nd (defective clusters), with the mean lifetime components ranging between 290 and 300 ps. Particle size estimation showed values from 8.6 to 28.9 nm. Along with the increase of neodymium impurities, also the conductivity increases, due to the hopping conduction mechanism between defective species. This gives rise to a response time of only 6 s, turning these materials candidates to realize gas sensor devices. Ab initio investigations showed that the improved electric conduction is boosted mostly by the reduced Nd2+ than the Ce3+, where the oxygen vacancies play a fundamental role. (AU)

• FAPESP's process: 18/20729-9 - Formation of Ag Nanoparticles by Laser Irradiation: An ab inicio Investigation
• Grantee: Luis Antônio Cabral
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 17/26105-4 - Multi-user equipment approved in grant 2016/23891-6 high performace computational cluster
• Grantee: Alex Antonelli
• Support Opportunities: Multi-user Equipment Program
• FAPESP's process: 16/23891-6 - Computer modeling of condensed matter
• Grantee: Alex Antonelli
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 13/07296-2 - CDMF - Center for the Development of Functional Materials
• Grantee: Elson Longo da Silva
• Support Opportunities: Research Grants - Research, Innovation and Dissemination Centers - RIDC
• FAPESP's process: 18/20590-0 - Novel renewable rare-earth based hybrid nanomaterials for environmental sensing and energy-related applications
• Grantee: Leandro Silva Rosa Rocha
• Support Opportunities: Scholarships in Brazil - Post-Doctoral