Semiconductor-metal transition in defect lithium cobaltite

The magnetic susceptibility, electrical conductivity, and x-ray photoelectron and x-ray absorption spectra of defect lithium cobaltites of the general formula Li 1 − x CoO 2 are investigated. It is found that, for lithium cobaltites with x > 0.25, the magnetic susceptibility increases abruptly and the conductivity type changes at T ∼ 150 K. The assumption is made that the semiconductor-metal transition in defect lithium cobaltite is caused by the increase in the diffusion mobility of lithium ions with an increase in the temperature when there is a correlation between spatial distributions of lithium vacancies and “electron” holes.