Solid-state synthesis and superior electrochemical performance of MnMoO4 nanorods for asymmetric supercapacitor

Abstract

Excellent stability and low synthetic cost of electrode materials are very important for the practical application of supercapacitors. Herein, an eco-friendly and extremely simple solid-state chemical synthetic strategy was used to construct the one-dimensional MnMoO4·0.9H2O (MMOH) and MnMoO4 (MMO) nanorods. Surprisingly, the obtained one-dimensional nanorods exhibited superior cycle stability as a supercapacitor electrode material. The long cycling life with 112.6% retention were obtained after 10,000 galvanostatic charge-discharge (GCD) cycles. In addition, the electrochemical properties of the obtained MnMoO4 were significantly improved after removing the crystal water in MnMoO4·0.9H2O, then the specific capacitance was increased by 2.4 times. When the power density reached 187.4 W kg−1 in asymmetric supercapacitor (ASC) device, the total cell exhibited an outstanding energy density of 23.5 Wh kg−1. The excellent electrochemical properties can be ascribed to the good electrical conductivity and more effective quality of active material for one-dimensional nanostructure after removing crystal water from MnMoO4·0.9 H2O. This work created a simple solvent-free method to construct one-dimensional MnMoO4 nanorods and provided a prospective electrode materials for supercapacitors.