Additive-free solvothermal synthesis and Li-ion intercalation properties of dumbbell-shaped LiFePO4/C mesocrystals

作者：Zhou, Nan; Wang, Hai-Yan; Uchaker, Evan; Zhang, Ming; Liu, Su-Qin; Liu, You-Nian^*; Cao, Guozhong

来源：Journal of Power Sources, 2013, 239: 103-110.

DOI：10.1016/j.jpowsour.2013.03.136

• Mesocrystals
• Lithium iron phosphate
• Self-assembly
• Lithium ion battery
• Cathode
• Nanorods

Hierarchical dumbbell-shaped lithium iron phosphate (LiFePO4) mesocrystals were successfully fabricated via a simple one-step, rapid, additive-free solvothermal route. A mixture of dimethylformamide/ethylene glycol (DMF/EG) has been utilized as the co-solvent and found to play an important role in the formation of the hierarchical mesostructure. The obtained dumbbell-shaped mesocrystals consist of self-assembly LiFePO4 nanorods each with 2-3 mu m in length and 30-50 nm in diameter. Further temperature treatment was applied to increase the crystallinity of the LiFePO4 mesocrystals. A high lithium ion intercalation capacity of 140 mA h g(-1) was exhibited by the LiFePO4 mesocrystal when tested under a discharge rate of 17 mA g(-1), which should be attributed to the fast intercalation reaction and easy mass and charge transfer offered by the large specific surface and short diffusion distance of dumbbell-shaped mesoporous composed of nano-sized LiFePO4 rods. The nanorods can be carbon coated in-situ by adding sucrose during the solvothermal process and the LiFePO4/C mesocrystals showed an improved electrochemical property at higher rates and good cyclic performance.

• 出版日期2013-10-1
• 单位中南大学