Zhang Hongyu, Ye Ke, Zhu Kai, Cang Ruibai, Yan Jun, Cheng Kui, Wang Guiling, Cao Dianxue
Key Laboratory of Superlight Materials and Surface Technology of, Ministry of Education, College of Materials Science and, Chemical Engineering, Harbin Engineering University, Harbin, 150001, P.R. China.
Chemistry. 2017 Dec 1;23(67):17118-17126. doi: 10.1002/chem.201703806. Epub 2017 Nov 7.
Porous FeVO is prepared by hydrothermal method and further modified by coating with carbon to obtain FeVO /C with a hierarchical pore structure. FeVO /C is used as an anodic electrode in aqueous rechargeable magnesium-ion batteries. The FeVO /C material not only has improved electrical conductivity as a result of the carbon coating layer, but also has an increased specific surface area as a result of the hierarchical pore structure, which is beneficial for magnesium-ion insertion/deinsertion. Therefore, an aqueous rechargeable magnesium-ion full battery is successfully constructed with FeVO /C as the anode, Mg-OMS-1 (OMS=octahedral molecular sieves) as the cathode, and 1.0 mol L MgSO as the electrolyte. The discharge capacity of the Mg-OMS-1//FeVO /C aqueous battery is 58.9 mAh g at a current density of 100 mA g ; this value is obtained by calculating the total mass of two electrodes and the capacity retention rate of this device is 97.7 % after 100 cycles, with almost 100 % coulombic efficiency, which indicates that the system has a good electrochemical reversibility. Additionally, this system can achieve a high energy density of 70.4 Wh kg , which provides powerful evidence that an aqueous magnesium-ion battery is possible.
采用水热法制备了多孔FeVO，并通过碳包覆进一步改性，得到具有分级孔结构的FeVO/C。FeVO/C用作水系可充电镁离子电池的阳极电极。FeVO/C材料不仅由于碳包覆层而提高了电导率，而且由于分级孔结构而增加了比表面积，这有利于镁离子的嵌入/脱出。因此，成功构建了以FeVO/C为阳极、Mg-OMS-1（OMS=八面体分子筛）为阴极、1.0 mol L MgSO为电解质的水系可充电镁离子全电池。Mg-OMS-1//FeVO/C水系电池在电流密度为100 mA g时的放电容量为58.9 mAh g；该值通过计算两个电极的总质量获得，该器件在100次循环后的容量保持率为97.7%，库仑效率几乎为100%，这表明该体系具有良好的电化学可逆性。此外，该体系可实现70.4 Wh kg的高能量密度，这为水系镁离子电池的可行性提供了有力证据。
