Synthesis and characterization of D-glucose derived nanospheric hard carbon negative electrodes for lithium- and sodium-ion batteries

The electrochemical performance of glucose-derived hard carbon (GDHC) anode has been evaluated using Li- and Na-salts in ethylene carbonate and propylene carbonate electrolyte mixtures. The LiPF6/EC:PC (1:1) system exhibits high capacity at low current densities (400 mAh g−1 at 25 mA g−1) and also good power characteristics retaining 150 mAh g−1 capacity at 2 A g−1 current density. The best overall performance was achieved with 1 M NaPF6/EC:PC (1:1) electrolyte based system with capacities of 175 mAh g−1 at 0.1 V vs Na/Na+ and 330 mAh g−1 at 1.5 V vs Na/Na+. The electrode has been physically characterized ex-situ using SEM, Raman and TOF-SIMS methods TOF-SIMS analysis revealed that the solid electrolyte interphase is more inorganic on the negative electrode in the Na-cell than on the negative electrode the Li-cell. The positive ion-specific images established by TOF-SIMS analysis show the non-homogeneous distribution of various fragments from the pristine GDHC, which is caused by slightly inhomogeneous mixture of GDHC and conducting carbon black (Super P®) particles

Carbon for Energy Storage Derived from Granulated White Sugar by Hydrothermal Carbonization and Subsequent Zinc Chloride Activation

© The Author(s) 2017. Published by ECS. This is an open access article distributed under the terms of the Creative Commons Attribution 4.0 License (CC BY). Various electrochemical methods have been applied to establish the electrochemical characteristics of the electrical double layer capacitor consisting of the activated carbon material based electrodes and 1 M triethylmethylammonium tetrafluoroborate solution in acetonitrile and 1-ethyl-3-methylimidazolium tetrafluoroborate ionic liquid as the electrolytes. Activated carbon material used for the preparation of electrodes has been synthesized from hydrochar prepared via hydrothermal carbonization process of granulated white sugar solution in H2O, followed by activation with ZnCl2with a mass ratio of 1:4 at the temperature 700°C. High porosity and Brunauer-Emmett-Teller specific surface area (SBET = 2100 m2g-1), micropore surface area (Smicro= 2080 m2g-1) and total pore volume (Vtot = 1.05 cm3g-1) have been achieved for the granulated white sugar derived carbon (GWS carbon) material. Wide region of ideal polarizability (ΔE ≤ 3.0 V), short characteristic relaxation time (0.5 s and 4.0 s), high specific series capacitance (125 F g-1and 140 F g-1) and high energy density (39 W h kg-1and 48 W h kg-1) have been calculated for the GWS carbon material in 1 M triethylmethylammonium tetrafluoroborate solution in acetonitrile and 1-ethyl-3-methylimidazolium tetrafluoroborate ionic liquid, respectively, demonstrating that these systems are very promising for energy storage devices

Different Carbide Derived Nanoporous Carbon Supports and Electroreduction of Oxygen

Using rotating disc electrode technique, the oxygen reduction reaction in 0.1M KOH was studied at various micromesoporous carbide derived carbon powders, synthesized from various binary metal carbides. The catalytic activity and mechanism noticeable depends on the hierarchical structure of the nanoporous carbon electrode. The activation with CO2 increases the differential volume of pores and proportion of mesopores in carbon matrix. It was shown that the partially graphitized carbon C Mo2C with a large number of edge plane sites has higher electrocatalytic activity toward oxygen reduction in alkaline media compared with other amorphous or partly graphitized carbons studied. The corresponding relative catalytic activity of catalysts increases in the following order C WTiC2 lt; Vulcan lt; C TiC lt; C TiC A1 amp; 8804; C TiC A2 lt; C Mo2C A lt; C Mo2C

The anti SARS-CoV-2 activity of nanofibrous filter materials activated with metal clusters

Nanofibrous filter materials were prepared by electrospinning a solution of 28 wt% poly(vinylidene fluoride) in N,N-dimethylacetamide with and without the addition of 2 wt% AgNO3, Cu(NO3)2·2.5H2O or ZnCl2. X-ray diffraction, scanning electron microscopy with energy dispersive X-ray spectroscopy, inductively coupled plasma mass spectroscopy, thermogravimetric analysis, contact angle measurement, nitrogen sorption, and mercury intrusion porosimetry methods were used for the characterization of physical structure as well as the chemical composition of the electrospun materials. Particle filtration efficiency and antiviral activity against the SARS-CoV-2 alpha variant were tested in order to estimate the suitability of the prepared electrospun filter materials for application as indoor air filtration systems with virucidal properties. All filter materials prepared with salts demonstrated very high particle filtration efficiency (≥98.0%). The best antiviral activity was demonstrated by a material containing Cu(NO3)2·2.5H2O in the spinning solution, which displayed the decrease in the number of infectious virions by three orders of magnitude after a contact time of 12 h. Materials with the addition of AgNO3 and ZnCl2 decreased the number of infectious virions after the same contact time by only ∼8 and ∼11 times, respectively