Acid-based modified NiCo₂O₄ as high-performance supercapacitor electrode materials

Abstract

The performance of supercapacitor electrode materials was greatly affected by the specific surface area. The urchin-like NiCo 2 O 4 was transformed into porous NiCo 2 O 4 (AA-NiCo 2 O[Formula: see text] using the acid–alkali treatment method. The specific surface area of AA-NiCo 2 O 4 was 165.0660 m 2 /g, which was about three times larger than that of NiCo 2 O 4 . The specific capacitance of the AA-NiCo 2 O 4 was enhanced significantly (1700 F/g at 1 A/g), and AA-NiCo 2 O 4 possesses good rate capacitance (1277 F/g at 10 A/g). This is mainly attributed to the larger specific surface area, fast and convenient electron–ion transport and redox reaction. Therefore, AA-NiCo 2 O 4 is a promising high-performance supercapacitor electrode material.