Wei Xijun, Song Yingze, Song Lixian, Liu Xu Dong, Li Yanhong, Yao Shuangrui, Xiao Peng, Zhang Yunhuai
State Key Laboratory of Environment-Friendly Energy Materials, School of Materials Science and Engineering, Southwest University of Science and Technology, Mianyang, 621010, P. R. China.
Research Centre of Laser Fusion, China Academy of Engineering Physics, Mianyang, 621900, P. R. China.
Small. 2021 Jan;17(4):e2007062. doi: 10.1002/smll.202007062. Epub 2020 Dec 23.
Porous carbon and metal oxides/sulfides prepared by using metal-organic frameworks (MOFs) as the precursors have been widely applied to the realm of supercapacitors. However, employing MOF-derived metal phosphides as positive and negative electrode materials for supercapacitors has scarcely been reported thus far. Herein, two types of MOFs are used as the precursors to prepare CoP and FeP nanocubes through a two-step controllable heat treatment process. Due to the advantages of composition and structure, the specific capacitances of FeP and CoP nanocubes reach 345 and 600 F g at the current density of 1 A g , respectively. Moreover, a quasi-solid-state asymmetric supercapacitor is assembled based on charge matching principle by employing CoP and FeP nanocubes as the positive and negative electrodes, respectively, which exhibits a high energy density of 46.38 Wh kg at the power density of 695 W kg . Furthermore, a solar-charging power system is assembled by combining the quasi-solid-state asymmetric supercapacitor and monocrystalline silicon plates, substantiating that the device can power the toy electric fan. This work paves a practical way toward the rational design of quasi-solid-state asymmetry supercapacitors systems affording favorable energy density and long lifespan.
以金属有机框架材料（MOFs）为前驱体制备的多孔碳和金属氧化物/硫化物已被广泛应用于超级电容器领域。然而，迄今为止，将MOF衍生的金属磷化物用作超级电容器的正负极材料鲜有报道。在此，使用两种类型的MOF作为前驱体，通过两步可控热处理工艺制备了CoP和FeP纳米立方体。由于组成和结构上的优势，在1 A g的电流密度下，FeP和CoP纳米立方体的比电容分别达到345和600 F g。此外，基于电荷匹配原理，分别以CoP和FeP纳米立方体作为正负极组装了准固态非对称超级电容器，在695 W kg的功率密度下，其能量密度高达46.38 Wh kg。此外，通过将准固态非对称超级电容器与单晶硅板相结合，组装了一个太阳能充电电源系统，证明该装置可为玩具电风扇供电。这项工作为合理设计具有良好能量密度和长寿命的准固态非对称超级电容器系统铺平了一条切实可行的道路。
