Electrical properties of the LaLiyCo1 – yO3 – δ (0 ≤ y ≤ 0.10) oxides

Resumo

The effect of the Li ion concentration on the phase composition, the electrical conductivity, and the thermoelectric power of the LaLi_yCo_1–yO_3–δ (0 ≤ y ≤ 0.1) oxides synthesized by cocrystallization has been studied. It is found that the region of the perovskite-like solid solution LaLi_yCo_1–yO_3–δ is no higher than y = 0.037. In the temperature range 300–1020 K, lithium alloying leads to an increase in the electrical conductivity and a decrease in the positive thermoelectric power of the single-phase samples compared to LaCoO_3–δ. The results are discussed using the density of states model proposed by Senarus Rodriguez and Goodenough for LaCoO_3–δ and La_1–xSr_xCoO_3–δ and using the Mott theory of noncrystalline substances.