Controllable synthesis of Ni1-xCoxMoO4 with tunable morphologies for high-performance asymmetric supercapacitors

Recently, elemental doping has proven to be an efficient method to improve the electrochemical per-formance of nanomaterials. In this work, we successfully synthesized Ni1-xCoxMoO4 with tunable morphologies through Co-doping by a facile chemical co-precipitation method, among which Ni0.85Co0.15MoO4 displays an excellent specific capacitance (1301 F g(-1) at 1 A g(-1)), which is higher than NiMoO4 electrode (1050.4 F g(-1) at 1 A g(-1)) and Ni0.7Co0.3MoO4 electrode (755.2 F g(-1) at 1 A g(-1)). In addition, Ni0.85Co0.15MoO4 electrode shows excellent cycling stability with 86% retention of its original capacitance after 3000 cycles. Additionally, an asymmetric supercapacitor (ASC) device can be fabricated using Ni0.85Co0.15MoO4/nickel foam (Ni0.85Co0.15MoO4/NF) as positive electrode and active carbon/nickel foam (AC/NF) as negative electrode. The as-fabricated ASC achieves a high energy density of 37.26 Wh kg(-1) at the power density of 400 W kg(-1), highlighting its potential application for the efficient energy storage devices. (C) 2020 Elsevier B.V. All rights reserved.

Automated summary

This study successfully synthesized Ni1-xCoxMoO4 nanomaterials with excellent electrochemical performance through elemental doping, among which Ni0.85Co0.15MoO4 showed superior specific capacitance. The asymmetric supercapacitor device fabricated using Ni0.85Co0.15MoO4 exhibited high energy density and cycling stability, highlighting its potential for efficient energy storage devices.