Mesoporous transition metal oxides quasi-nanospheres with enhanced electrochemical properties for supercapacitor applications

摘要

In this report, we obtain mesoporous transition metal oxides quasi-nanospheres (includes MnO2, NiO, and Co3O4) by utilizing mesoporous silica nanospheres as a template for high-performance supercapacitor electrodes. All samples have a large specific surface area of approximately 254-325 m(2) g(-1) and a relatively narrow pore size distribution in the region of 7 nm. Utilization of a nanosized template resulted in a product with a relative uniform morphology and a small particle diameter in the region of 50-100 nm. As supercapacitor electrodes, MnO2, NiO, and Co3O4 exhibit an outstanding capacity as high as 838-1185 F g(-1) at 0.5 A and a superior long-term stability with minimal loss of 3-7% after 6000 cycles at 1 A g(-1). Their excellent electrochemical performances are attributed to favorable morphologies with a large surface area and a uniform architecture with abundant pores. The associated enhancement of electrolyte ion circulation within the electrode facilitates a significant increase in availability of Faradic reaction electroactive sites. (C) 2016 Elsevier Inc. All rights reserved.