Defect engineering of vanadium pentoxide for efficient lithium-ion storage. (10th February 2020)

• Record Type: Journal Article
• Authors: Hu, Mingxiang; Liu, Zhaohui; Zhang, Hongwei; Huang, Zheng-Hong; Kang, Feiyu; Lv, Ruitao
• Is Part Of: Electrochimica acta. Volume 333(2020)
• Publication Date: 2020-02-10
• Subjects: Vanadium oxide -- Lithium-ion battery -- Sonication method -- Amorphous structure; Electrochemistry -- Periodicals; Electrochemistry, Industrial -- Periodicals; 541.37
• DOI: 10.1016/j.electacta.2019.135513
• Languages: English
• ISSNs: 0013-4686

Abstract

Abstract: Developing high-performance cathode materials for lithium-ion batteries (LIBs) is very crucial for the practical applications. Vanadium pentoxide (V2 O5 ), an intrinsic pseudocapacitive material with tunneled structure, possesses high theoretical capacity (294 mAh g −1, 2–4 V vs. Li + /Li) in LIBs by reversible phase changes from two Li + insertion/extraction. However, the sluggish diffusion of Li + in V2 O5 lattice and the poor electron conductivity cause a large gap between its practical capacity and the theoretical value. Defect engineering is a regulation method at the atomic scale of crystal materials to achieve the properties that intrinsic materials do not have. Herein, based on defect engineering, a unique V2 O5 cathode material with amorphous and crystalline symbiosis structure is synthesized via a sonication method which demonstrates superior electrochemical performances. As cathode material for LIB, the optimized sample (N1K2) delivers one of the most competitive capacities of ∼400 mAh g −1 at 0.02 A g −1 and 193 mAh g −1 at 3 A g −1 . This high capacity can be attributed to the increased exposure of (001) planes, the abundant ion storing sites at the interfaces and in percolation channels in the amorphous structures. A high capacity of 175 mAh g −1 with a retention of 81.8% (0.036% decay per cycle) can be also achieved after 500 cycles under 2 A g −1 . Therefore, sonochemistry might serve as a promising way for defect engineering of crystalline materials to boost their properties in electrochemical energy storage or other fields.