Sepiolite/amorphous nickel hydroxide hierarchical structure for high capacitive supercapacitor

Abstract

Abstract Sepiolite/amorphous nickel hydroxide (SEP/Ni(OH)2) hierarchical structures consist of sepiolite (SEP) fibers and amorphous Ni(OH)2 nanosheets have been synthesized successfully via a facile, scalable co-reduction method as excellent performance supercapacitor. SEP fibers are provided as a matrix for the attachment and diffusion of Ni(OH)2 nanosheets. The effects of the combination of SEP and Ni(OH)2 on the morphology, structure, and electrochemical performance of SEP/Ni(OH)2 are discussed comprehensively. When the molar ratio of SEP and Ni(OH)2 is 1:8, the specific capacitance of SEP/Ni(OH)2 reaches 2050\xa0F\xa0g-1 at the current density of 1\xa0A\xa0g-1, which is approximately 53 times larger than that of the pure SEP. Moreover, the SEP/Ni(OH)2-8//AC (active carbon) asymmetric supercapacitor represent a prominent energy density of 24\xa0Wh\xa0kg-1 at a power density of 950\xa0W\xa0kg-1. A red LED (1.8-2\xa0V) and a yellow LED (1.9-2.4\xa0V) can be lighted easily. The enhanced electrochemical performance of SEP/Ni(OH)2 is ascribed to its high surface area and high charge transfer rate for amorphous porous structure.