Year: 2020
Type: article
Abstract: We fabricate Sm-doped Ca3Co4O9+δ (CCO) bulk materials in magnetic field during both processes of chemical synthesis and cold pressing. The structure and electrical performance of the samples are investigated. With the increasing Sm concentration, the electrical conductivity 1/ρ decreases and the Seebeck coefficient α increases. As a result, the power factor (PF = α 2/ρ) is raised slightly. After applying magnetic field, the extent of texture, grain size and density of all the bulk materials are improved obviously, thereby an enhanced electrical conductivity can be gained. Additionally, the degeneracy of Co4+ state in the CoO2 layer of CCO is also increased as the magnetic field is used in the preparing process, which results in an enhanced α. The Ca2.85Sm0.15Co4O9+δ prepared in magnetic field shows the largest power factor (0.20 mW⋅m−1⋅K−2 at 1073 K).
Source: Chinese Physics B
Authors: Xiu-Rong Qu, Yan-Yan Xu, Shu-Chen Lü, Jian-Min Hu
Institutions: Harbin Normal University, Dalian University of Technology
Language: English
Subfield: Materials Chemistry
Field: Materials Science
Domain: Physical Sciences
Open Access status: bronze
Award: G4474321434
OpenAlex ID: W3006261487