Uniform porous spinel NiCo2O4 with enhanced electrochemical performances

The electrochemical performances of uniform porous NiCo2O4 nanoparticles obtained through a template- free co-precipitation way were explored in details, revealing that NiCo2O4 electrode prepared by NaHCO3 has a great advantage over that fabricated by NaOH, resulting in more uniform and higher porous nanostructures, which manifests a superior specific capacitance of 726.8 F g(-1) at 1 A g(-1) and a better cycle stability of 72.7% retention at 5 A g(-1) after 2000 cycles. The enhanced pseudocapacitive performances can mainly be ascribed to well-distributed mesoporous structure coming from the releasing of CO2 that primely prevents the agglomeration of the nanocrystals. Therefore, it can be a promising candidate to substitute the routine precipitant of NaOH for the preparation of some other binary or even ternary metal oxides for supercapacitors. (C) 2015 Elsevier B.V. All rights reserved.