Progress of Nanostructured Electrode Materials for Supercapacitors

Abstract

Supercapacitors, as a type of energy storage system, bridge the power/energy gap between conventional capacitors and batteries due to attractive properties such as high power density, long cycle lifespan, and large temperature range. However, the low energy density of supercapacitors compared to lithium‐ion batteries has hindered their general application. In general, the electrochemical performance of supercapacitors is closely related to the structure of their electrode materials, electrolytes, and device design. The main materials used in electrochemical double‐layer capacitors (EDLCs) are carbon materials with various architectures. This is due to their high surface area, good electric conductivity, and intrinsic stability. In this review, recently reported carbon‐based nanostructured electrode materials with 0D, 1D, 2D, and 3D structures are systematically reviewed. The effect of nanostructuring on the properties of supercapacitors including specific capacitance, rate capability, and cycle stability is explored, the details of which may serve as a guide to electrode design for the next generation of EDLCs.

Sodium‐ion capacitors: Materials, Mechanism, and Challenges

“…In light of this, researchers have attempted to design carbon materials with various structures ranging from 1 D to 3 D to expand the specific surface area and further enhance the capacitance. In an earlier review, we summarized the progress of nanostructured carbon materials and discussed the influence of morphology on their electrochemical properties . Recently, biomass‐ or organic compound‐derived carbons, graphene, and CNTs, for example, have been employed as cathode materials for SICs.…”

Redox‐Mediator‐Enhanced Electrochemical Capacitors: Recent Advances and Future Perspectives

“…[7] Commercial supercapacitors (electrochemical double-layer capacitors, EDLCs) with two porousc arbon electrodes show ah igh powerd ensity. [5,8,9] As shown in the Figure 1b,E DLCs store energy through the adsorption/desorptiono fo ppositely charged ions at the interface of carbons. EDLCs with high powerd ensity and long cyclel ife can complement or substituteb atteries in some situations requiring ahigh power delivery.…”

“…However, because of the sluggish ion diffusion in the solid materials, batteries have a low power density, which cannot satisfy the need of high output . Commercial supercapacitors (electrochemical double‐layer capacitors, EDLCs) with two porous carbon electrodes show a high power density . As shown in the Figure b, EDLCs store energy through the adsorption/desorption of oppositely charged ions at the interface of carbons.…”

Nanoengineered Skeleton‐surface of Nickel Foam with Additional Dual Functions of Rate‐capability Promotion and Cycling‐life Stabilization for Nickel Sulfide Electrodes

“…Supercapacitors (SCs) are one category of attracting energy storage devices for the application in some burgeoning areas such as portable electronics, hybrid electric vehicles, smart electricity grids storing the intermittent energy, etc. [1][2][3][4][5][6][7] The two basic types of SCs including electrical double layer capacitors (EDLCs) and Faraday supercapacitors (FSs) present their own featured electrochemical mechanisms of energy storage and release. The mechanism of electrostatic attraction at the carbon/electrolyte interface is the source of the high power density and low energy density signature of EDLCs, [8,9] and yet the mechanism of faradaic redox reaction of FSs leads to its converse signature.…”