NixCo1-x,(OH)2 nanosheets on carbon nanofoam paper as high areal capacity electrodes for hybrid supercapacitors

This work reports the charge storage ability of NixCo(1-x)(OH)(2) nanosheet-carbon nanofoam paper (CNFP) composites prepared by electrodeposition for high areal capacity supercapacitor electrodes. The NixCo1-x (OH)(2) film grew through instantaneous nucleation, uniformly covered CNFP, and displayed a porous morphology composed of a nanosheet percolation network. The electrochemical response of the NixCo1-x x(OH)(2) films was tuned by varying the Co to Ni ratios. The optimized NixCo1-x(OH)(2) stoichiometry resulted in Ni0.33Co0.67(OH)(2)-CNFP electrodes displaying areal capacity/capacitance values of 1.52 C cm(-2)/2.03 F cm(-2) at 2.1 mA cm(-2), resulting from the contribution of the double layer capacity of CNFP with the redox capacity of NixCo(1-x)(OH)(2). A two electrode cell composed of CNFP as negative electrode and NixCo(1-x)(OH)(2)-CNFP as positive electrode presented a high areal capacity value of 0.73 C cm(-2) at 7.2 mA cm(-2). (C) 2017 Elsevier Ltd. All rights reserved.