Interlayer‐Spacing‐Regulated VOPO4 Nanosheets with Fast Kinetics for High‐Capacity and Durable Rechargeable Magnesium Batteries. Issue 32 (25th June 2018)

• Record Type: Journal Article
• Authors: Zhou, Limin; Liu, Qi; Zhang, Zihe; Zhang, Kai; Xiong, Fangyu; Tan, Shuangshuang; An, Qinyou; Kang, Yong‐Mook; Zhou, Zhen; Mai, Liqiang
• Is Part Of: Advanced materials. Volume 30:Issue 32(2018)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2018-06-25
• Subjects: diffusion kinetics -- interlayer spacing -- magnesium batteries -- VOPO4 nanosheets; Materials -- Periodicals; Chemical vapor deposition -- Periodicals; 620.11
• DOI: 10.1002/adma.201801984
• Languages: English
• ISSNs: 0935-9648

Abstract

Abstract: Owing to the low‐cost, safety, dendrite‐free formation, and two‐electron redox properties of magnesium (Mg), rechargeable Mg batteries are considered as promising next‐generation secondary batteries with high specific capacity and energy density. However, the clumsy Mg 2+ with high polarity inclines to sluggish Mg insertion/deinsertion, leading to inadequate reversible capacity and rate performance. Herein, 2D VOPO4 nanosheets with expanded interlayer spacing (1.42 nm) are prepared and applied in rechargeable magnesium batteries for the first time. The interlayer expansion provides enough diffusion space for fast kinetics of MgCl + ion flux with low polarization. Benefiting from the structural configuration, the Mg battery exhibits a remarkable reversible capacity of 310 mAh g −1 at 50 mA g −1, excellent rate capability, and good cycling stability (192 mAh g −1 at 100 mA g −1 even after 500 cycles). In addition, density functional theory (DFT) computations are conducted to understand the electrode behavior with decreased MgCl + migration energy barrier compared with Mg 2+ . This approach, based on the regulation of interlayer distance to control cation insertion, represents a promising guideline for electrode material design on the development of advanced secondary multivalent‐ion batteries. Abstract : VOPO4 nanosheets with expanded interlayer spacing endow the architecture with MgCl + insertion, featuring decreased polarization compared with Mg 2+ and substantially enhancing ion‐diffusion dynamics. Benefiting from the dominant configuration, the VOPO4 nanosheets deliver a reversible capacity of 192 mAh g −1 at 100 mA g −1 even after 500 cycles and remarkable rate capability.