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.

Nowadays numerous sorbents based on graphene and other carbon nanomaterials have been synthesized for the removal or collecting of oil remains due to its unique physico-chemical properties. Obtaining of aerogels based on graphene oxide and carbon nanotubes with addition of chitosan solution as a binder component is shown in this paper. Aerogels were synthesized by reduction of aqueous dispersion of graphene oxide using the reducing agents, followed by ultrasonic and thermal treatment. Ultrasound destroys the graphene layers, decreasing them in size, thereby exposing new layers to form edges that already have no stabilizing carboxyl groups, which are located at the edges, and participate in the formation of bonds. The surface morphology of obtained aerogels was studied by SEM. The study of the sorption capacity showed that graphene/CNTs aerogel is characterized by short absorption time and high sorption ability that depend on densities of the used solvents. All experimental results show the possibility of using the aerogels based on graphene and CNTs as sorbents for collection of oil residues.

Rare earth materials exhibit unique hydrogen storage properties compared to other materials due to their distinct electron shell structure. Among them, rare earth nanomaterials possess higher specific surface areas, and a greater number of reactive active sites compared to traditional rare earth materials, leading to more stable and superior adsorption processes. Regarding the preparation methods and morphology control of rare earth nanomaterials, this article introduces preparation techniques such as solid-phase, liquid-phase, and vapor-phase methods. It discusses the influencing factors and control strategies of different methods on nanomaterial morphology, analyzes the advantages and disadvantages of each method and the research progress in different countries and regions. Simultaneously, it summarizes the applications of rare earth nanomaterials in solid-state hydrogen storage, electrochemical hydrogen storage, liquid hydrogen storage, catalytic combustion, and other areas. This study examines the relationship between preparation routes, morphological control and hydrogen storage performance, with particular emphasis on rare-earth-based nanomaterials. It highlights the challenges and prospects for their practical application in energy storage. The mechanisms of rare earth hydrogen storage and achieved research results are summarized. Prospects for the development of the rare earth nanomaterials field are also presented.