Hollow Co_0.85Se Nanowire Array on Carbon Fiber Paper for High Rate Pseudocapacitor

Abstract

A supercapacitor electrode is fabricated with Co0.85Se hollow nanowires (HNW) array, which is synthesized by wet chemical hydrothermal selenization of initially grown cobalt hydroxyl carbonate nanowires on conductive CFP. The dense self-organized morphology of Co0.85Se HNWs is revealed by scanning/transmission electron microscopy. The as-synthesized Co0.85Se HNWs possess high pseudocapacitive property with high capacitance retention and high durability. The areal capacitance value is seen to vary from 929.5 to 600 mF cm(-2) (60% retention) as the current density is increased from 1 to 15 mA cm(-2), an increase of a factor of 15. Based on mass loading, this corresponds to a very high gravimetric capacitance of 674 (for 2 mA cm(-2) or 1.48 Ag(-1)) and 444 Fg(1-) (for 15 mA cm(-2) or 11 A g(-1)) in a full-cell configuration with the Co0.85Se HNWs as cathode and activated carbon as anode (asymmetric configuration) promising results are obtained.

Design and synthesis of Ni-MOF/CNT composites and rGO/carbon nitride composites for an asymmetric supercapacitor with high energy and power density

“…It is worth noting that the specific capacitance sharply increases at the initial 500 cycles, which is probably related to the activation of the active materials. [56] The indistinct appearance of the semicircle indicates a very low charge transfer resistance at the electrode/electrolyte interface than the initial cycle, which is ascribed to better wettability facilitating the better electrolyte diffusion and charge transfer. Such cycling performance is highly competitive with those results of some other asymmetric supercapacitors (ESI , Table Sl).…”

A novel aqueous asymmetric supercapacitor based on petal-like cobalt selenide nanosheets and nitrogen-doped porous carbon networks electrodes

“…4a shows the cyclic voltammetry (CV) curves of the Co 0.85 Se nanosheets as positive electrode at scan rates ranging from 5 to 30 mV s À1 in the potential window of À0.1e0.65 V. The Co 0.85 Se nanosheets electrode exhibits two pairs of redox peaks, indicating it has typical Faradaic pseudocapacitance behavior. The redox peaks corresponding to the reversible redox reaction could be expressed as [19]:…”

“…As a class of metal selenides, cobalt selenide is also known as a metallic conductor and widely used as transparent counter electrodes for dye-sensitized solar cells [15], electrocatalyst for the oxygen evolution reaction [16e18] and so on. However, to the best of our knowledge, still little attention has been paid to the cobalt selenide as electrode materials for supercapacitor so far [19].…”

Hydrothermal assisted in situ growth of CoSe onto graphene nanosheets as a nanohybrid positive electrode for asymmetric supercapacitors

“…25 However, to the best of our knowledge, very few attempts have been made so far to use cobalt selenide as an electrochemical supercapacitor electrode material 26,27 and no data has been reported on the use of cobalt selenide-graphene nanohybrid for the asymmetric supercapacitor application.…”