3D nanoflower-like zinc hydroxyl carbonates for high performance asymmetric supercapacitors

Abstract

Recently, it is essential to design and fabricate efficient electrode materials for energy storage devices. In this work, nanoflower–like Zn5(OH)6(CO3)2 assembled from ultrathin sheets are successfully grown on NF by a one pot hydrothermal method. The Zn5(OH)6(CO3)2 electrode exhibits superior specific capacitance of 3.36 F cm−2 (2240.7 F g−1) at 2 A g−1 in 1 M KOH electrolyte, and the cycling test is measured and still remain 96.9% of initial capacitance after 6000 cycles. In addition, an asymmetric supercapacitor (ASC) is assembled, which shows excellent electrochemical performance with specific capacitance of 56.5 F g−1 at 0.5 A g−1 and excellent cycle stability (91.9% retention of initial capacitance after 6000 cycles). In a word, the high performance can be attributed to the 3D nanoflower-like structure and the Zn5(OH)6(CO3)2 is a promising candidate in energy storage devices.