Chain-like NiCo2O4 nanowires with different exposed reactive planes for high-performance supercapacitors

Abstract

Faceted crystals with different exposed planes have attracted intensive investigations for applications.Herein, we report a facile hydrothermal and thermal decomposition process which is successfully developed to grow 3D NiCo 2 O 4 micro-spheres constructed with radial chain-like NiCo 2 O 4 nanowires with different exposed crystal planes. When applied as electrode materials for supercapacitors, chainlike NiCo 2 O 4 nanowires exhibit excellent electrochemical performances in supercapacitors with high specific capacitance (1284 F g À1 at 2 A g À1 ), good rate capability, and excellent cycling stability (only 2.5% loss after 3000 cycles). In situ electrical properties clearly illustrated that the chain-like nanowires with different exposed crystal planes exhibit excellent electronic conductivity, which shows that the electronic conductivity plays an essential role for electrode materials in supercapacitors. So, high electronic conductivity chain-like NiCo 2 O 4 nanowires with different exposed crystal planes can form a competitive electrode material for next generation supercapacitors.

Spinel NiCo₂O₄ Nanorods for Supercapacitor Applications

“…Recently, there has been growing interest in nanostructured materials with specific morphology like three dimensional (3D) urchins, (Wang et al, 2012b) two dimensional (2D) nanosheets (Zhang and Lou, 2013) and one dimensional (1D) nanoneedles, nanowires (Zhu et al, 2013) and nanorods (Salunkhe et al, 2011) for their possible application as supercapacitor electrodes due to their enhanced electrochemical properties, high specific surface area and availability of short electron and ion transport pathways (Zou et al, 2013). Two dimensional transition metal oxides (TMOs) like RuO 2 , (Zang et al, 2008) Co 3 O 4 , (Xia et al, 2011) NiO (Zhang et al, 2010 and Mn 3 O 4 (Dubal et al, 2009) have been widely studied as electrodes for supercapacitors.…”

Integrating large specific surface area and high conductivity in hydrogenated NiCo2O4 double-shell hollow spheres to improve supercapacitors

“…4 Thus, more and more attentions were focused on pseudocapacitive electrode materials because their energy density associated with Faradaic reactions is much larger than that of electrochemical double-layer capacitors. [5][6][7][8] To improve performances of pseudocapacitors, two crucial factors are usually considered for the electrode materials, they are large specific surface area and high conductivity for electrolyte ions and electrons. On the one hand, large specific surface area will provide more electroactive sites for the Faradaic reactions, and load more doublelayer charges.…”

Hierarchically nanostructured transition metal oxides for supercapacitors

“…Nickel cobaltite exhibits excellent electrochemical performance because of richer redox reaction between nickel and cobalt ions [118]. A variety of nickel cobaltite materials with different morphologies, such as NPs [119], nanowires [120,121], urchin-like shape [122], and hollow spheres [123], have been studied as electrode materials for SCs.…”