The Metal-Insulator Transition of Na_0.8Co_1-xSm_xO₂

Abstract

The effects of the Sm ions doping on the structure, electronic transport and magnetic properties of Na 0.8 CoO 2 have been investigated. Single-phase samples of Na 0.8 Co 1-x Sm x O 2 (0 ≤ x ≤ 0.15) have been synthesized. It has been found that the c-axis lattice parameters increase with Sm ions doping. 5% Sm doping leads to metal-insulator transition and the pseudo Kondo effects at low temperature in Na 0.8 Co 1-x Sm x O 2 .

Electronic Structure and Thermoelectric Power Factor of Na x CoO 2 from First-Principles Calculation

“…[12] Moreover, doped atoms could lead to a metal-insulator transition at low temperature in Na 0.8 Co 1−𝑥 Sm 𝑥 O 2 . [13] The formation energies of defects and the resultant changes in electronic structure of Na 𝑥 CoO 2 were evaluated using first-principles calculation. [14] In addition, the thermoelectric properties of the Na 𝑥 CoO 2 were also investigated using a simple lattice dynamical model or the Boltzmann theory.…”