Recent Progress in Co₃O₄‐Based Nanomaterials for Supercapacitors

Abstract

Supercapacitors which have been widely used in portable electronics and hybrid electric vehicles are considered to be fascinating energy storage devices owing to their higher energy density than traditional capacitors and higher power density than batteries. The performance of supercapacitors is much dependent on the properties of the used electrode materials, and much effort has been devoted to exploring high‐performance electrodes. During the past decade, cobalt‐based materials, especially Co3O4 and its composites, have been regarded as prominent electrode materials for supercapacitors in view of their relatively low cost, high theoretical specific capacitance, non‐toxicity, and excellent electrochemical activity. In this review, we attempt to provide some basic insights into the rational design of Co3O4 based materials/composites and their capacitive properties for supercapacitors. The electrochemical advantages of Co3O4 as a supercapacitor material are summarized, and many examples are illustrated. The remaining challenges in exploration of Co3O4‐based materials as efficient electrodes for supercapacitors are also discussed and the future research directions are offered.

Deep eutectic solvents as an emerging green platform for the synthesis of functional materials

“…22c and d). 174,175 Zhang et al 176 published a one-step pyrolysis process for the direct in situ production of DES/NC@CC as precursors for ultrathin, nanosized nitrogen-doped carbon (NC) composites of Co 4 N (Fig. 22e).…”

Nanotechnology in Advanced 2D and 3D Nanostructured Transition Metal Oxide Based Flexible Supercapacitors: A Review

“…[111][112][113] However, the poor electrical conductivity reduces the electrochemical stability. [114] Co 3 O 4 exhibits a variety of morphological characteristics and extremely porous structures that aid in the facilitation of charge storage in electrochemical SC. [115] The charge storage reaction of CO 3 O 4 in KOH is represented as shown in Eqn.…”

“…Co 3 O 4 is the most commonly used electrode material among other cobalt oxide groups in electrical energy storage systems because it is low‐cost, naturally abundant, environmentally safe, and exhibits two oxidation states (Co 2+ and Co 3+ ), strong redox activity, high theoretical specific capacitance (3560 F/g), and higher corrosion resistance [111–113] . However, the poor electrical conductivity reduces the electrochemical stability [114] . Co 3 O 4 exhibits a variety of morphological characteristics and extremely porous structures that aid in the facilitation of charge storage in electrochemical SC [115] .…”

Sodium‐Substituted Tungsten Oxide Nanoflowers: An Efficient Electrode Enhancing the Pseudocapacitive Storage in Aqueous Asymmetric Supercapacitors

“…are highly suitable for the supercapacitor because of their pseudocapacitive charge storage and various oxidation states. [8][9][10][11][12] Among the TMO materials, WO 3 is the most promising electrode material for the pseudocapacitor because of several oxidation states (W + 2 to W + 6 ), different crystal structures, tunable morphology, and nontoxic properties. [13,14] The crystal structure of the polymorph of WO 3 shows the cubic ReO 3 type structure.…”

“…TMO materials such as NiO, WO 3 , MoO 3 , Fe 3 O 4 , Co 3 O 4 etc. are highly suitable for the supercapacitor because of their pseudocapacitive charge storage and various oxidation states [8–12] …”