Publications by authors named "Aleksandrs Volperts"

Carbonization of biomass residues followed by activation has great potential to become a safe process for the production of various carbon materials for various applications. Demand for commercial use of biomass-based carbon materials is growing rapidly in advanced technologies, including in the energy sector, as catalysts, batteries and capacitor electrodes. In this study, carbon materials were synthesized from hardwood using two carbonization methods, followed by activation with HPO, KOH and NaOH and doping with nitrogen.

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Biorefineries with the significant amounts of lignin as a by-product have a potential to increase business revenues by using this residue to produce high value-added materials. The carbon materials from biomass waste increases the profitability of the production of porous carbon used for sorbents and energy production. The purpose of this research is to study the chemical properties of lignin from "Sweetwoods" biorefinery as well as to characterize lignin carbonizates and activated carbons synthesized from them.

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Nitrogen-doped activated carbons with controlled micro- and mesoporosity were obtained from wood and wastes via chemical processing using pre-treatment (pyrolysis at 500 °C and hydrothermally carbonization at 250 °C) and evaluated as oxygen reduction catalysts for further application in fuel cells. The elemental and chemical composition, structure and porosity, and types of nitrogen bonds of obtained catalyst materials were studied. The catalytic activity was evaluated in an alkaline medium using the rotating disk electrode method.

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Herein, we present a synthesis route for high-efficiency nitrogen-doped carbon materials using kraft pulping residue, black liquor, and wood charcoal as carbon sources. The synthesized nitrogen-doped carbon materials, based on black liquor and its mixture with wood charcoal, exhibited high specific surface areas (SSAs) of 2481 and 2690 m g, respectively, as well as a high volume of mesopores with an average size of 2.9-4.

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In this recent decade, great interest has risen to develop metal-free and cheap, biomass-derived electrocatalysts for oxygen reduction reaction (ORR). Herein, we report a facile strategy to synthesize an electrochemically active nanocarbon material from the renewable and biological resource, wood biomass. The ORR activity of the catalyst material was investigated in 0.

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