RECENT ADVANCES AND CHALLENGES OF CURRENT COLLECTORS FOR SUPERCAPACITORS

Global energy and environmental issues are driving the development of modern advances in efficient and environmentally friendly energy storage systems. Such systems must meet a range of requirements, which include high energy and power density, long service life, flexibility, industrial scalability, security and reliability. Progressive achievements in the field of energy storage are associated with the development of various kinds of batteries and supercapacitors. Supercapacitors are state-of-the-art energy storage devices with high power density, long lifespan, and the ability to bridge the power/energy gap between conventional capacitors and batteries/fuel cells. However, supercapacitors have limitations associated with low energy density, which can be solved by using various types of current collectors, since current collectors are one of the main massive components of supercapacitors. This review gives a complete understanding of the effect of current collectors on the actual performance and properties of supercapacitors. We reviewed current collectors based on carbon and metal-containing materials, and supercapacitor configurations to identify possible improvements in electrochemical performance in terms of specific capacitance, energy density, power density, service life and variability in their application

EFFECTIVENESS OF BIO-WASTE-DERIVED CARBON DOPING ON DE-ICING PERFORMANCE OF AN ELECTRICALLY RESISTANT CONCRETE

This paper proposes a modified carbon-based concrete filler composition, which can potentially be used as a self-de-icing pavement. Carbon fibers (CNFs), graphene-like porous carbon (GLC), and a CNF/GLC composite were developed to reinforce concrete with the aim to improve its electrical conductivity and mechanical properties. The effect of the CNF and GLC loadings on the electrical conductivity of the filled concrete was evaluated in a climatic chamber at temperatures simulating water-freezing conditions on a concrete road. The results show that even a negligible loading (0.2 wt.%) of concrete with CNF/GLC results in a dramatic decrease in its resistance when compared to the same loadings for CNF and GLC added separately. Depending on the number of fillers, the temperature of the modified concrete samples reached up to +19.8 °C at low voltage (10 V) at −10 °C, demonstrating the perspective of their heat output for anti-icing applications. Additionally, this study shows that adding 2.0 wt.% of the CNF/GLC composite to the concrete improves its compressive strength by 33.93% compared to the unmodified concrete

Process of Obtaining Chromium Nitride in the Combustion Mode under Conditions of Co-Flow Filtration

In this work, the combustion process of chromium powder in the co-flow filtration mode was studied. The effect of nitrogen-containing gas flow rate on the nitridation of combustion products is shown. The effect of the amount of argon in the nitrogen–argon mixture on the burning rate and the burning temperature of the chromium powder is shown. It was found that an increase in the percentage of argon in the nitrogen–argon mixture can lead to the formation of an inverse combustion wave. The actual burning temperature is higher than adiabatic burning temperature in the co-flow filtration mode, thus the phenomenon of superadiabatic heating is observed. The phase composition of the obtained combustion products was studied. It was shown that the forced filtration mode allows for synthesizing non-stoichiometric Cr2N nitride

Modification of Biomass-Derived Nanoporous Carbon with Nickel Oxide Nanoparticles for Supercapacitor Application

Supercapacitors are one of the promising devices for the accumulation and storage of electrical energy. The purpose of this study is to develop a synthesis and modification method of carbon material to improve the electrochemical characteristics of a supercapacitor. In the proposed study, by varying the sequence and parameters of the processes of carbonization, mechanoactivation and thermochemical activation, the conditions for obtaining nanoporous carbon with a specific surface area of 2200 (±50) m2/g from walnut shells (WSs) are optimized. In addition, to increase the electrochemical efficiency of the electrode material, the resulting nanoporous carbon was modified with nickel oxide (NiO) nanoparticles by the thermochemical method. It is shown that the modification with nickel oxide nanoparticles makes it possible to increase the specific capacitance of the supercapacitor electrode by 16% compared to the original unmodified nanoporous carbon material