Clay minerals modified nickel boride for electrochemical supercapacitor electrode application

Abstract

Nickel boride has attracted great interest in the field of energy storage due to its superior electrochemical performance, However, particles agglomeration and poor electability have limited its wider application. Clay minerals with high specific surface area and excellent wettability can reduce the agglomeration of particles. We synthesized eight kinds of composites Ni3B@montmorillonite (Ni3B@Mt), Ni3B@chlorite (Ni3B@Chl), Ni3B@vermiculite (Ni3B@Ver), Ni3B@kaolinite (Ni3B@Kaol), Ni3B@palygorskite (Ni3B@Pal), Ni3B@halloysite (Ni3B@Hal), Ni3B@sepiolite (Ni3B@Sep), and Ni3B@talc (Ni3B@Tal) materials with different morphologies and structures by simple liquid phase reduction method. We explored the influence of a series of clay minerals on the electrochemical performance of Ni3B. The results show that the specific capacitance of the Ni3B@clay minerals composites has been improved in different degrees. In addition, the Ni3B@Mt. shows the best specific capacitance of 1406 F g−1 at a current density of 0.5 A g−1, and still maintains a high specific capacitance of 944 F g−1 at a current density of 5 A g−1. The assembled asymmetric supercapacitor Ni3B@Mt.//AC using an activated carbon (AC) and the Ni3B@Mt. showed excellent electrochemical performance with achieving the maximum energy density of 92.60 W h kg−1 at the power density of 350 W kg−1, which suggests the practical application of clay minerals in the electrochemical energy storage field.