title: Highly Crystallized Na₂CoFe(CN)₆ with Suppressed Lattice Defects as Superior Cathode Material for Sodium-Ion Batteries.
abstract: Prussian blue and its analogues have received particular attention as superior cathodes for Na-ion batteries due to their potential 2-Na storage capacity (∼170 mAh g(-1)) and low cost. However, most of the Prussian blue compounds obtained from the conventional synthetic routes contain large amounts of Fe(CN)6 vacancies and coordinated water molecules, which leads to the collapse of cyano-bridged framework and serious deterioration of their Na-storage ability. Herein, we propose a facile citrate-assisted controlled crystallization method to obtain low-defect Prussian blue lattice with greatly improved Na-storage capacity and cycling stability. As an example, the as-prepared Na2CoFe(CN)6 nanocrystals demonstrate a reversible 2-Na storage reaction with a high specific capacity of 150 mAh g(-1) and a ∼ 90% capacity retention over 200 cycles, possibly serving as a low cost and high performance cathode for Na-ion batteries. In particular, the synthetic strategy described in this work may be extended to other coordination-framework materials for a wide range of energy conversion and storage applications.
authors: College of Chemistry and Molecular Science, Wuhan University , Wuhan 430072, China.
authors: Xianyong
authors: X
authors: Wu
authors: College of Chemistry and Molecular Science, Wuhan University , Wuhan 430072, China.
authors: Chenghao
authors: C
authors: Wu
authors: College of Chemistry and Molecular Science, Wuhan University , Wuhan 430072, China.
authors: Congxiao
authors: C
authors: Wei
authors: College of Chemistry and Molecular Science, Wuhan University , Wuhan 430072, China.
authors: Ling
authors: L
authors: Hu
authors: College of Chemistry and Molecular Science, Wuhan University , Wuhan 430072, China.
authors: Jiangfeng
authors: J
authors: Qian
authors: College of Chemistry and Molecular Science, Wuhan University , Wuhan 430072, China.
authors: Yuliang
authors: Y
authors: Cao
authors: College of Chemistry and Molecular Science, Wuhan University , Wuhan 430072, China.
authors: Xinping
authors: X
authors: Ai
authors: School of Chemistry and Chemical Engineering, Shanghai Jiao Tong University , Shanghai, 200240, China.
authors: Jiulin
authors: J
authors: Wang
authors: College of Chemistry and Molecular Science, Wuhan University , Wuhan 430072, China.
authors: Hanxi
authors: H
authors: Yang
keywords: Prussian blue framework; controlled crystallization method; lattice defects; sodium cobalt hexacyanoferrate; sodium-ion batteries