Kangwon National University

About: Kangwon National University is a education organization based out in Chuncheon, South Korea. It is known for research contribution in the topics: Population & Catalysis. The organization has 9836 authors who have published 20002 publications receiving 393562 citations. The organization is also known as: KNU.

Evaluation of phosphorus adsorption capacity of sesame straw biochar on aqueous solution: influence of activation methods and pyrolysis temperatures

Abstract: The phosphorus (P) adsorption characteristic of sesame straw biochar prepared with different activation agents and pyrolysis temperatures was evaluated. Between 0.109 and 0.300 mg L−1 in the form of inorganic phosphate was released from raw sesame straw biochar in the first 1 h. The release of phosphate was significantly enhanced from 62.6 to 168.2 mg g−1 as the pyrolysis temperature increased. Therefore, sesame straw biochar cannot be used as an adsorbent for P removal without change in the physicochemical characteristics. To increase the P adsorption of biochar in aqueous solution, various activation agents and pyrolysis temperatures were applied. The amount of P adsorbed from aqueous solution by biochar activated using different activation agents appeared in the order ZnCl2 (9.675 mg g−1) > MgO (8.669 mg g−1) ⋙ 0.1N-HCl > 0.1N-H2SO4 > K2SO4 ≥ KOH ≥ 0.1N-H3PO4, showing ZnCl2 to be the optimum activation agent. Higher P was adsorbed by the biochar activated using ZnCl2 under different pyrolysis temperatures in the order 600 °C > 500 °C > 400 °C > 300 °C. Finally, the amount of adsorbed P by activated biochar at different ratios of biochar to ZnCl2 appeared in the order 1:3 ≒ 1:1 > 3:1. As a result, the optimum ratio of biochar to ZnCl2 and pyrolysis temperature were found to be 1:1 and 600 °C for P adsorption, respectively. The maximum P adsorption capacity by activated biochar using ZnCl2 (15,460 mg kg−1) was higher than that of typical biochar, as determined by the Langmuir adsorption isotherm. Therefore, the ZnCl2 activation of sesame straw biochar was suitable for the preparation of activated biochar for P adsorption.

Mechanically compliant and lithium dendrite growth-suppressing composite polymer electrolytes for flexible lithium-ion batteries

Abstract: We demonstrate mechanically compliant and lithium dendrite growth-suppressing composite polymer electrolytes for use in flexible lithium-ion batteries This new composite polymer electrolyte (referred to as “CPE”) is fabricated via an exquisite combination of UV (ultraviolet)-cured ethoxylated trimethylolpropane triacrylate macromer (serving as a mechanical framework) and Al2O3 nanoparticles (as a functional filler) in the presence of a high boiling point liquid electrolyte A distinctive structural feature of the CPE is the close-packed Al2O3 nanoparticles in the liquid electrolyte-swollen ETPTA macromer matrix Owing to this unique morphology, the CPE provides significant improvements in the mechanical bendability and suppression of lithium dendrite growth during charge–discharge cycling