Hierarchical three-dimensional NiMoO.sub.4-anchored rGO/Ni foam as advanced electrode material with improved supercapacitor performance

• Published in: Journal of materials science 2018-06, Vol.53 (11), p.8483
• Main Authors: Xu, Yuekui, Xuan, Haicheng, Gao, Jinhong, Liang, Ting, Han, Xiaokun, Yang, Jing, Zhang, Yongqing
• Format: Article
• Language: English
• Subjects: Capacitors; Electric properties; Electrochemical reactions; Electrochemistry; Electrolytes; Graphene
• ISSN: 0022-2461; 1573-4803
• DOI: 10.1007/s10853-018-2171-1

Designing a novel, efficient and cost-effective nanocomposite with the advantage of robust structure and outstanding conductivity is highly promising for the electrode materials of high-performance supercapacitors. Herein, we designed and synthesized a hierarchical structured NiMoO.sub.4@rGO/NF via a facile and scalable approach by growing NiMoO.sub.4 nanowires onto the skeleton of reduced graphene oxide (rGO)/Ni foam (NF). The as-made NiMoO.sub.4@rGO/NF exhibits a superior electrochemical behavior owing to the coupling effect of homogeneous NiMoO.sub.4 nanowires and high conductivity of rGO, and it exhibits a superb capacitance value of 1877 F g.sup.-1 at 1 A g.sup.-1 and shows a ultralong life span with over 98% capacitance retention after 4000 cycles at 5 A g.sup.-1 in 2 M KOH electrolyte. Moreover, an asymmetric device employing NiMoO.sub.4@rGO/NF composite and activated carbon is assembled with an aqueous electrolyte, and it displays a maximum energy density of 40 Wh kg.sup.-1 at a specific power 218.2 W kg.sup.-1. Interestingly, the asymmetric device can remain 111.2% of its initial value even after 8000 charge/discharge cycles. These results demonstrate that the NiMoO.sub.4@rGO/NF binder-free electrode provides greatly enhanced electrochemical performance and shows promising application as an anode for energy storage.