Abstract
The MoN nanoparticles in the size range of 20-30 nm are dispersed onto the surface of nitrogen doped CNT (MoN/N-CNT) by annealing at 600 degrees C kept under a constant flow of nitrogen gas for 4 hr. The N doping of CNT is confirmed from the characteristic Raman shift. The as-synthesized nanoparticles display hexagonal MoN phase with sharp mesoporous internal structure and a high surface area of 369 m(2) g(-1). As an anode material, the composite structure demonstrates high reversible capacity, long cycle life and excellent rate performance. A reversible capacity of 1232 mAh g(-1) is maintained after 200 cycles at a current density of 100 mA g(-1). When the electrode is tested at higher current densities of 1000, 1250 and 1500 mA g(-1) for 20 cycles each, it still holds a high specific capacity of 1184.7,1096.5 and 989.5 mAh g(-1). This electrochemical performance is also compared with bare MoN, N-CNT, MoO2 and MoO2/functionalized-CNT anodes. The superior electrochemical performance is credited to the nitrogen doping of CNT which reduce the charge transfer resistance along with the higher conductivity of MoN due to the substitution of oxygen octahedral sites of MoO2 with nitrogen atoms. (C) 2015 Elsevier Ltd. All rights reserved.