Construction of advanced 3D Co3S4@PPy nanowire anchored on nickel foam for high-performance electrochemical energy storage

Rational designed electrodes with high electron and ion diffusion capability is of great significant for the high-performance energy storage devices. Herein, the 3D Co3S4@PPy nanowires anchored on nickel foam (NF) was fabricated by a facile hydrothermal route and followed polymerization process. The vertically aligned Co3S4 nanowires are uniformly anchored on the NF struts without obvious aggregation, while the PPy is tightly encapsulated on the Co3S4 surface with a fluffy and porous structure. Therefore, the Co3S4@PPy hybrid electrode with bi-continuous conductive networks, NF struts and PPy coating layer, and porous PPy coating layer can facilitate electrons transfer as well as decrease electrolyte ions diffusion pathway. This hybrids as the electrochemical electrode exhibit the battery-type behavior, and an ultrahigh specific capacity of 723 C g(-1), good rate capability and excellent cycling durability (98.6% retention after 1000 cycles) can be achieved. Moreover, the asymmetric two-electrode devices assembled by the Co3S4@PPy and active carbon (AC) can deliver a high practical performance in aqueous system. The material design strategy would provide an efficient way to develop high-performance energy storage devices. (C) 2020 Elsevier Ltd. All rights reserved.