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The original version of this Data Descriptor omitted the following information from the Acknowledgements.

Основной целью настоящей работы было получение высокоплотного сверхтвердого керамического материала на основе карбида бора спеканием под высоким давлением без использования активирующих добавок. Исследованы микроструктура, плотность и твердость по Виккерсу образцов, спеченных из порошков карбида бора различной дисперсности при давлении 4 ГПа в интервале температур 1200 – 2000 °С. Основною метою цієї роботи було отримання високоякісного надтвердого керамічного матеріалу на основі карбіду бору спіканням під високим тиском без використання активуючих добавок. Досліджені мікроструктура, щільність і твердість по Віккерсу зразків, спечених з порошків карбіду бору різної дисперсності при тиску 4 ГПа в інтервалі температур 1200–2000 °С. The main purpose of this work was to obtain a high-density superhard ceramic material based on boron carbide by sintering under high pressure without the use of activating additives. The microstructure, density and Vickers hardness of samples sintered from boron carbide powders of various dispersities at a pressure of 4 GPa in the temperature interval 1200–2000 °C were investigated.

The efficient storage of energy combined with a minimum carbon footprint is still considered one of the major challenges towards the transition to a progressive, sustainable and environmental friendly society on a global scale. The energy storage in pure chemical form using gas carriers with high heating values, including H-2 and CH4, as well as via electrochemical means using state-of-the-art devices, such as batteries or supercapacitors, are two of the most attractive alternatives for the combustion of finite, carbon-rich and environmentally harmful fossil fuels, such as diesel and gasoline. A few-step, reproducible and scalable method is presented in this study for the preparation of an ultra-microporous (average pore size around 0.6 nm) activated carbon cloth (ACC) with large specific area ( GT 1200 m(2)/g) and pore volume (similar to 0.5 cm(3)/g) upon combining chemical impregnation, carbonization and CO2 activation of a low-cost cellulose-based polymeric fabric. The ACC material shows a versatile character towards three different applications, including H2 storage via cryo-adsorption, separation of energy-dense CO2/CH4 mixtures via selective adsorption and electrochemical energy storage using super-capacitor technology. Fully reversible H-2 uptake capacities in excess of 3.1 wt% at 77 K and similar to 72 bar along with a significant heat of adsorption value of up to 8.4 kJ/mol for low surface coverage have been found. Upon incorporation of low-pressure sorption data in the ideal adsorbed solution theory model, the ACC is predicted to selectively adsorb about 4.5 times more CO2 than CH4 in ambient conditions and thus represents an appealing adsorbent for the purification of such gaseous mixtures. Finally, an electric double-layer capacitor device was assembled and tested for its electrochemical performance, constructed of binder-free and flexible ACC electrodes and aqueous CsCl electrolyte. The full-cell exhibits a gravimetric capacitance of similar to 121 F/g for a specific current of 0.02 A/g, which relative to the ACCs specific area, is superior to commercially available activated carbons. A capacitance retention of more than 97% was observed after 10,000 charging/discharging cycles, thus indicating the ACCs suitability for demanding and high-performance energy storage on a commercial scale. The enhanced performance in all tested applications seems to be attributed to the mean ultra-micropore size of the ACC material instead of the available specific area and/or pore volume.

Hexagonal boron nitride (h-BN) nanoplatelets with similar to 99 wt.% purity, 900 to 2000 nm particle width, 30 to 90 nm particle thickness, similar to 213 m(2)/g specific surface area (SSA), similar to 66% micropore SSA and similar to 0.85 nm average pore size were synthesized in a powder form using H3BO3 and CO(NH2)(2) as precursors followed by consecutive thermal treatments under inert and oxidized atmospheres. Thermal gravimetric analysis (TGA) combined with differential scanning calorimetry (DSC), under synthetic air-flow and up to similar to 1300 degrees C, were employed to evaluate both purity and oxidation resistance of the product directly upon its synthesis. The h-BN powder was collected at the stage of its highest purity which, based on TGA-DSC data, corresponded to an additional heat treatment up to similar to 700 degrees C. The active oxidation seems to occur in the temperature range between similar to 860 and similar to 1000 degrees C, followed by formation of B2O3 in the final residue. Subsequently, the purified h-BN powder was extensively characterized for its structure, morphology and porosity using X-ray diffraction, scanning electron microscopy and nitrogen gas adsorption/desorption measurements at 77 respectively. As briefly discussed, purity and SSA seem to have a crucial role in the thermal stability and oxidation resistance of BN materials in general. (C) 2016 Elsevier Ltd. All rights reserved.