Carbon Nanocages as Supercapacitor Electrode Materials

Abstract

Supercapacitor electrode materials: Carbon nanocages are conveniently produced by an in situ MgO template method and demonstrate high specific capacitance over a wide range of charging-discharging rates with high stability, superior to the most carbonaceous supercapacitor electrode materials to date. The large specific surface area, good mesoporosity, and regular structure are responsible for the excellent performance.

Microwave-Assisted Oxidation of Electrospun Turbostratic Carbon Nanofibers for Tailoring Energy Storage Capabilities

“…It is known that for carbon materials the capacitance values obtained with the two different electrode configurations are similar, [36] whereas for conducting polymers the results given by the two different electrode systems are usually disparate. [89] A detailed comparison between the two electrode configurations has been given by Stoller and Ruoff.…”

“…[15,[63][64][65][66][67][68][69][70][71][72][73][74][75] Furthermore, at such a high scan rate (i.e., 0.1 V/s), the capacitance value of ECNF-M3 compared favorably to those of many other carbon-based supercapacitor materials, including conventional systems such as mesoporous carbon (ca. 150 F/g) [37][38][39] and activated carbon (<120 F/g), [40][41][42] as well as recently reported carbon nanomaterials such as carbon nanocages (185 F/g), [36] carbon nanococoons (175 F/g), [43] and graphene (ca. 150 -200 F/g).…”

“…All profiles were recorded after 10 CV cycles at 0.1 V/s. The operation voltage was adjusted such that in this potential range the galvanostatic curve exhibited a quasi-triangular form; [36,37] the optimized operation cell voltage was 1 V for all samples. Among the four samples, ECNF-M3 exhibited the longest charge/discharge time, indicating the highest capacitance.…”

“…Carbonaceous materials are well-known examples of DL capacitive materials. [2,35] However, carbon-based electrocapacitive systems usually exhibit moderate specific capacitances, especially at high operation rates; for many carbon systems of various forms, [36][37][38][39][40][41][42][43][44][45][46][47] the optimal capacitance value obtained at a high scan rate of 0.1 V/s or at a high current density of 1 A/g is typically 50-150 F/g, and rarely exceeds 200 F/g. Nonetheless, carbon electrodes are still the most popular choice to date for use in commercial supercapacitor devices due to their ease of synthesis, low cost, and exceptional chemical and electrochemical stability.…”

Design of 3D Graphene‐Oxide Spheres and Their Derived Hierarchical Porous Structures for High Performance Supercapacitors

“…For instance, sacrificial templates were utilized as a backbone to prepare hierarchical structures. [40,41] In addition, different types of molecular nanostructures were inserted between graphene sheets as spacers to facilitate charge transport and storage. [42][43][44] Apart from surface area, pore volume and pore-size distribution across micropore (<2 nm), mesopore (2-50 nm), and macropore (>50 nm) regimes (a hierarchical pore structure) play a crucial role in facilitating ion storage, transport, and distribution.…”