Transport Properties in (Na,Ca)Co2O4 Ceramics
Abstract
The resistivity and thermopower of polycrystalline (Na,Ca)Co2O4 were measured and analyzed. Both the quantities increase with x, suggesting that the carrier density is decreased by the substitutions of Ca2+ for Na+. Considering that the temperature dependence of the resistivity show a characteristic change with x, the conduction mechanism is unlikely to come from a simple electron-phonon scattering. As a reference for NaCo2O4, single crystals of a two-dimensional Co oxide (Bi,Pb)2M3Co2O9 (M=Sr and Ba) were studied. The Pb substitution decreases the resistivity, leaving the thermopower nearly intact.
Turn this paper into a full lesson
ArcXiv compiles a staged curriculum from this paper: 8-12 lessons across beginner → advanced, synthesised section guides, visuals, flashcards, a quiz, exercises, and on-demand deep dives per section. Grounded in the abstract, never invented.