Effect of Niobium Doping on the Properties of Molybdenum Sulfides as Cathode Materials

摘要

Poorly crystalline molybdenum sulfides are promising candidates as cathode materials which require good electronic and ionic conductivity. Poorly crystalline molybdenum sulfide films with a large range of sulfur contents were successfully synthesized by the activated reactive evaporation technique. Raman spectra of the poorly crystalline films showed dual structure characteristics corresponding to 2H-MoS2 and amorphous MoS3. The films with the above structure demonstrated significantly improved intercalation ratios of lithium atoms, thereby enhancing the energy density of the secondary lithium batteries. However, the current density was lower because of the high electronic resistivity of the films. Niobium, acting as an acceptor, was, therefore, doped into the molybdenum sulfide films to decrease the electronic resistivity. Decrease in the resistivity by about three orders of magnitude was observed. Keywords: Reprints; Cathodes. (kt)