2D Ti3C2 nanosheets, multilayer structures, and conical scrolls produced by room temperature exfoliation of Ti3AlC2 in HF are reported. Since Ti3AlC2 is a member of a 60+ group of layered ternary carbides and nitrides, this discovery opens a door to the synthesis of a large number of other 2D crystals.

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from carbides has attracted special attention lately. [ 3,4 ] Carbide-derived carbons (CDCs) encompass a large group of carbons ranging from extremely disordered to highly ordered structures ( Figure 1 ). The carbon structure that results from removal of the metal or metalloid atom(s) from the carbide depends on the synthesis method (halogenation, hydrothermal treatment, vacuum decomposition, etc.), applied temperature, pressure, and choice of carbide precursor.The growing interest in this fi eld is refl ected by a rapidly increasing number of publications and patents. A signifi cant progress in CDC research has been seen in several fi elds. Various carbide precursors have been systematically studied. Studies on binary carbides with different grain sizes show the possibility of low-temperature carbon formation for nanopowders. Also, a better understanding of graphene formation during high-temperature vacuum decomposition of silicon carbide has been achieved since SiC single crystals are now available in large sizes with extremely low defect concentrations and an almost atomically fl at surface fi nish. [ 8 ] CDC applications as electrode materials in electric double layer capacitors have attracted much attention lately. [ 9 ] The unique properties of porous CDC obtained by halogenation, such as a high specifi c surface area and tunable pore size with a narrow size distribution, make it an ideal material for sorbents or supercapacitor electrodes. CDCs have been derived from many precursors (SiC, TiC, Mo 2 C, VC, etc.) using a variety of treatment conditions that lead to a broad range of useful properties. Furthermore, graphene, [ 10 ] nanotubes, [ 11 ] and even nanodiamond [ 12 ] can be produced from carbide precursors. Their applications naturally differ from those of porous CDC.The last comprehensive journal review on this subject was published about fi fteen years ago in Russian; [ 13 ] book chapters published later [ 3,4 , 14 ] are less accessible and require updating due to rapid progress in the fi eld over the past few years. The most recent review of CDC [ 14 ] covers only energy-related applications. Therefore, a comprehensive review on the fi eld is long overdue. The goal of this article is to show how a variety of carbon structures can be produced from carbides, to explain how those structures can be controlled on the nanometer and subnanometer scale, and to describe CDC properties that are benefi cial for a number of applications. Carbide-Derived Carbons -From Porous Networks to Nanotubes and GrapheneCarbide-derived carbons (CDCs) are a large family of carbon materials derived from carbide precursors that are transformed into pure carbon via physical (e.g., thermal decomposition) or chemical (e.g., halogenation) processes. Structurally, CDC ranges from amorphous carbon to graphite, carbon nanotubes or graphene. For halogenated carbides, a high level of control over the resulting amorphous porous carbon structure is possible by changing the synthesis conditions and carbide precursor. The large number of...

This paper describes a flexible and lightweight fabric supercapacitor electrode as a possible energy source in smart garments. We examined the electrochemical behavior of porous carbon materials impregnated into woven cotton and polyester fabrics using a traditional printmaking technique (screen printing). The porous structure of such fabrics makes them attractive for supercapacitor applications that need porous films for ion transfer between electrodes. We used cyclic voltammetry, galvanostatic cycling and electrochemical impedance spectroscopy to study the capacitive behaviour of carbon materials using nontoxic aqueous electrolytes including sodium sulfate and lithium sulfate. Electrodes coated with activated carbon (YP17)

Continuous carbidederived carbon films with high volumetric capacitance. (2011) Energy & Environmental Science, 4 (1). 135.