Sol-gel synthesis of normal spinel LiMn₂O₄ and its characteristics

Abstract

Normal spinel LiMn₂O₄ was synthesized by sol-gel method using lithium nitrate, manganese nitrate, citric acid and ethylene glycol as raw materials. LiMn₂O₄ was characterized by XRD, TG-DTA, IR, SEM and AAS. The optimum conditions for the synthesis were explored. Citric acid and ethylene glycol were mixed with molar ratio of 0.25, and the mixture was esterified at 140°C for 4 hours. Then lithium nitrate and manganese nitrate were added with molar ratio of 0.6. In the system, the total molar of cations was equal to that of citric acid. At last, reflux the system at 105°C for 2 hours. Dried gel was fired at 600°C for 8 hours. Particle diameters of raw product were about 100 nm mainly. Further research shows that lithium ion of LiMn₂O₄ is easy to be extracted, and normal spinel λ-MnO₂ can be obtained after lithium ion extraction.

Keywords

sol-gel method / synthesis of LiMn₂O₄ / λ-MnO₂

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