NiMoO4 nanorod deposited carbon sponges with ant-nest-like interior channels for high-performance pseudocapacitors
By Yunpeng Huang, Fen Cui, Yan Zhao, Jiabiao Lian,Jian Bao, Tianxi Liu and Huaming Li
Published in Inorganic Chemistry Frontiers
2018
Abstract
The mounting challenges of global energy shortage and climate change call for the development of low-cost and high performance energy storage systems. Here, we propose the facile preparation of a 3D sponge electrode material by the uniform deposition of NiMoO4 nanorods on a carbonized melamine sponge (CMS) during a solvothermal reaction. Under the templating of a macroporous CMS backbone, the obtained 3D hierarchical NiMoO4/CMS composite sponge can offer numerous electrochemical sites for faradaic redox reactions and also provide interconnected conducting carbon networks for direct and rapid charge transfer. Particularly, the unique ant-nest-like interior channels in the NiMoO4/CMS composite sponge can ensure fast ion transportation and also buffer the volume change of NiMoO4 during the long-term cycling. Benefiting from these advantages, the NiMoO4/CMS composite electrode exhibits a high specific capacitance of 1689 F g−1 at 1 A g−1, which outperforms most of the previously reported NiMoO4-based electrodes. Moreover, the asymmetric supercapacitor device fabricated utilizing the composite sponge as a binder-free positive electrode also delivers a superior cycling stability (91.9% capacity retention after 2500 cycles) and a high energy density of 48.8 W h kg−1 at a power density of 800 W kg−1. Hence, the current study provides a new protocol for the low-cost fabrication of 3D sponge-like electrodes towards practical supercapacitor applications.