There is significant interest in high-performance materials that can directly and efficiently capture water vapor, particularly from air. Herein, we report a class of novel porous carbon cuboids with unusual ultra-hydrophilic properties, over which the synergistic effects between surface heterogeneity and micropore architecture is maximized, leading to the best atmospheric water-capture performance among porous carbons to date, with a water capacity of up to 9.82 mmol g(-1) at P/P0 =0.2 and 25 °C (20% relative humidity or 6000 ppm). Benefiting from properties, such as defined morphology, narrow pore size distribution, and high heterogeneity, this series of functional carbons may serve as model materials for fundamental research on carbon chemistry and the advance of new types of materials for water-vapor capture as well as other applications requiring combined highly hydrophilic surface chemistry, developed hierarchical porosity, and excellent stability.

Silica nanospheres are used as templates for the generation of carbide-derived carbons with monodisperse spherical mesopores (d=20-40 nm) and microporous walls. The nanocasting approach with a polycarbosilane precursor and subsequent pyrolysis, followed by silica template removal and chlorine treatment, results in carbide-derived carbons DUT-86 (DUT=Dresden University of Technology) with remarkable textural characteristics, monodisperse, spherical mesopores tunable in diameter, and very high pore volumes up to 5.0 cm3 g(-1). Morphology replication allows these nanopores to be arranged in a nanostructured inverse opal-like structure. Specific surface areas are very high (2450 m2 g(-1)) due to the simultaneous presence of micropores. Testing DUT-86 samples as cathode materials in Li-S batteries reveals excellent performance, and tailoring of the pore size allows optimization of cell performance, especially the active center accessibility and sulfur utilization. The outstanding pore volumes allow sulfur loadings of 80 wt %, a value seldom achieved in composite cathodes, and initial capacities of 1165 mAh gsulfur(-1) are reached. After 100 cycle capacities of 860 mAh gsulfur(-1) are retained, rendering DUT-86 a high-performance sulfur host material.

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Polymer-based silicon carbide-derived carbons (Si-CDCs) synthesized at temperatures from 600 to 1500 °C using different templating methods were characterized by wide-angle x-ray scattering (WAXS), Raman spectroscopy, and transmission electron microscopy (TEM). A recently developed advanced algorithm for fitting the whole WAXS data curve of non-graphitic carbons, that is, carbons with a polyaromatic sp2 structure, revealed fine details about the CDC microstructure on the level of the graphene layers. In particular, this approach allowed the quantification of disorder effects in the graphene stacks and the clarification of the peculiarity of CDCs. It is seen that, contrary to other types of carbons, almost no stacking of the sp2 layers occurs; that is, the stack height L c is rather small (8 Å) and increases only slightly with higher synthesis temperatures, whereas the graphene layer extent L a grows significantly, from 16 to 29 Å. Additionally, the microstructures of various types of CDCs were investigated: a hexagonal CDC and a cubic ordered mesoporous CDC, as well as a macroporous CDC. The WAXS analysis reveals that soft-templated CDCs, featuring macroporosity with an average wall thickness of hundreds of nm, show a more uniform stacking order than mesoporous CDCs obtained by hard-templating, with an average wall thickness of a few nanometers.

Carbide-derived carbon (CDC) aerogel monoliths with very high porosity are synthesized starting from polymeric precursors. Cross-linking by platinum-catalyzed hydrosilylation of polycarbosilanes followed by supercritical drying yields preceramic aerogels. After ceramic conversion and silicon extraction in hot chlorine gas, hierarchically porous carbon materials with specific surface areas as high as 2122 m2 g-1 and outstanding total pore volumes close to 9 cm3 g-1 are obtained. Their pore structure is controllable by the applied synthesis temperature as shown by combined nitrogen (-196 [degree]C) and carbon dioxide (0 [degree]C) measurements coupled with electron microscopic methods. The combination of large micropore volumes and the aerogel-type pore system leads to advanced adsorption properties due to a combination of large storage capacities and effective materials transport in comparison with purely microporous reference materials as shown by thermal response measurements