3D hierarchical CoWO4/Co3O4 nanowire arrays for asymmetric supercapacitors with high energy density

• Published in: Chemical engineering journal (Lausanne, Switzerland : 1996) Switzerland : 1996), 2018-09, Vol.347, p.291-300
• Main Authors: Zhang, Mingchang, Fan, Huiqing, Zhao, Nan, Peng, Haijun, Ren, Xiaohu, Wang, Weijia, Li, Hua, Chen, Guangyu, Zhu, Yangni, Jiang, Xinbiao, Wu, Peng
• Format: Article
• Language: English
• Subjects: 3D CoWO4/Co3O4 nanowire arrays; Cobalt oxide (Co3O4); Electrode; Microwave hydrothermal; Supercapacitors
• ISSN: 1385-8947; 1873-3212
• DOI: 10.1016/j.cej.2018.04.113

We first synthesized a 3D hierarchical CoWO4/Co3O4 nanowire arrays material for supercapacitors. The 3D CoWO4/Co3O4//AC ASCs device shows high energy density and power density. [Display omitted] •We first found that CoWO4 and 3D CoWO4/Co3O4 exhibit four pairs of redox peaks and discussed it systematically.•We first synthesized a 3D CoWO4/Co3O4 nanowire arrays materials.•The integration of CoWO4 enhances the activity of the redox reaction.•The 3D CoWO4/Co3O4//AC ASCs device shows high energy density and power density. A 3D hierarchical CoWO4/Co3O4 structure, with the synergetic effect of diverse materials, large specific surface area and fast transmission of electrons and ions is synthesized by a facile and efficient microwave hydrothermal method. We found that CoWO4 and 3D CoWO4/Co3O4 exhibit four pairs of redox peaks, which were discussed systematically. The hybrid electrode shows excellent specific capacitance of 1728 F g−1 at current density of 2.7 mA cm−2 (1 A g−1) with superior rate capability and satisfactory cycling stability (85.9% capacitance preserved after 5000 cycles). The asymmetric supercapacitors assembled with CoWO4/Co3O4 and activated carbon exhibit high energy density (57.8 Wh kg−1) and power density (6000 W kg−1 at 40.64 Wh kg−1), with remarkable cycle life. The above results indicate that the ordered CoWO4/Co3O4 nanowire arrays synthesized by this approach would be a promising candidate for practical application of high-performance supercapacitors.