Not just graphene: The wonderful world of carbon and related nanomaterials

Abstract

Carbon, with its variety of allotropes and forms, is the most versatile material, and virtually any combination of mechanical, optical, electrical, and chemical properties can be achieved with carbon by controlling its structure and surface chemistry. The goal of this article is to help readers appreciate the variety of carbon nanomaterials and to describe some engineering applications of the most important of these. Many different materials are needed to meet a variety of performance requirements, but they can all be built of carbon. Considering the example of supercapacitor electrodes, zero-and onedimensional nanoparticles, such as carbon onions and nanotubes, respectively, deliver very high power because of fast ion sorption/desorption on their outer surfaces. Twodimensional (2D) graphene offers higher charge/discharge rates than porous carbons and a high volumetric energy density. Three-dimensional porous activated, carbide-derived, and templated carbon networks, with high surface areas and porosities in the angstrom or nanometer range, can provide high energy densities if the pore size is matched with the electrolyte ion size. Finally, carbon-based nanostructures further expand the range of available nanomaterials: Recently discovered 2D transition-metal carbides (MXenes) have already grown into a family with close to 20 members in about four years and challenge graphene in some applications.

Exploring High‐Energy Li‐I(r)on Batteries and Capacitors with Conversion‐Type Fe3O4‐rGO as the Negative Electrode

“…To improve the electrical transport characteristics, carbon‐coated magnetite materials and composites formulated with advanced carbonaceous materials such as carbon nanotubes and reduced graphene oxide (rGO) have been reported ,,. In addition, the electrochemical performance of metal oxides on 2D graphene is dramatically improved with smaller nanoparticles of more uniform size ,. However, it is very challenging to design a simple synthesis strategy to ensure a well‐controlled nanocomposite because of the multiple steps and time‐consuming nature of these synthesis processes.…”

“…Hence, we have chosen cost effective, LiFePO 4 as cathode by compromising the working potential. Similarly, in the case of utilization of such high capacity negative electrodes in LIC is a hot topic of research along with activated carbon (AC) as counter electrode ,. This is probably because of the intrinsic electrical conductivity, limited rate performance and poor cycle stability .…”

Biomass‐Derived Carbon Materials as Prospective Electrodes for High‐Energy Lithium‐ and Sodium‐Ion Capacitors

“…Typically, electrical double‐layer capacitors (EDLCs), often called supercapacitors, are fabricated from high‐surface‐area carbonaceous materials in the presence of aqueous solution. To date, a variety of carbonaceous materials, that is, allotropes such as graphene, porous carbon materials, carbon nanotubes (single, double, and multi‐walled), and aerogels, have been explored as supercapacitors, but activated carbon (AC) remains the most‐popular choice for prospective electrodes . In a typical configuration, high‐surface‐area carbonaceous materials form a double layer across an electrode/electrolyte interface through the accumulation of charge carriers over the surface.…”

“…To date, av ariety of carbonaceous materials, that is,a llotropes such as graphene, porous carbon materials,c arbon nanotubes (single, double, and multi-walled), and aerogels, have been explored as supercapacitors, but activated carbon (AC) remains the most-popular choicef or prospective electrodes. [2][3][4][5] In at ypical configuration, high-surface-area carbonaceous materials form ad ouble layer across an electrode/electrolyte interface through the accumulation of charge carriers over the surface. Such physical adsorption/desorption,t hat is, double-layer formation, certainly translates high power capability to the system.…”

Processing of Onion-like Carbon for Electrochemical Capacitors

“…1 Carbon black or carbon nanotubes are often added to the activated carbon and other electrode materials to improve their electronic conductivity and performance at high rates. 2 Another carbon material, onion-like carbon (OLC) has also shown promise in electrochemical capacitors because of a unique, multishell fullerene structure with nanoscale diameters (5-10 nm). [3][4][5][6][7][8] OLC can be considered as the ultimate carbon black because of its small particle size and high electrical conductivity.…”