Rational Assembly of CoAl‐Layered Double Hydroxide on Reduced Graphene Oxide with Enhanced Electrochemical Performance for Energy Storage.

Autor: Liang, Ting, Xuan, Haicheng, Xu, Yuekui, Gao, Jinhong, Han, Xiaokun, Yang, Jing, Han, Peide, Wang, Dunhui, Du, Youwei
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Zdroj: ChemElectroChem; Sep2018, Vol. 5 Issue 17, p2424-2434, 11p
Abstrakt: Abstract: In this paper, we designed and synthesized composites of CoAl‐layered double hydroxide on reduced graphene oxide (CoAl‐LDH@rGO/NF) via a facile approach. The Co‐Al layered double hydroxide (CoAl‐LDH) nanosheets were grown onto the skeleton of reduced graphene oxide on Ni foam (rGO/NF). The as‐synthesized CoAl‐LDH@rGO/NF composites exhibited a superior electrochemical behavior, attributed to the coupling effect of homogeneous CoAl‐LDH nanosheets and high conductivity of rGO. In addition, the different morphologies of the CoAl‐LDH@rGO/NF composites can be controlled by adjusting the amount of NH4F. The optimum electrochemical performance of the CoAl‐LDH@rGO/NF hybrid electrode was obtained when the amount of NH4F was 6 mmol. The largest specific capacitance of 1671.4 F g−1 (1 A g−1) and the ultra‐high cycling performance with 97 % retention of the original value were achieved even after 5000 charge‐discharge cycles. A remarkable energy density value of 41.3 Wh kg−1 at a power density of 408.9 W kg−1 was achieved in the asymmetric supercapacitor (ASC) using CoAl‐LDH@rGO‐6/NF and activated carbon (AC) for positive and negative materials. Furthermore, the ASC retained 100 % of its original energy density value even after 5000 cycles. In addition, a design method for preparing high performance electrode materials with ideal morphology is proposed in this paper, which might be helpful to the future study of morphology and electrochemical properties. [ABSTRACT FROM AUTHOR]
Databáze: Complementary Index
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