Solid oxide fuel cells (SOFC) are promising, environmentally friendly energy sources. Many works are devoted to the study of materials, individual aspects of SOFC operation, and the development of devices based on them. However, there is no work covering the entire spectrum of SOFC concepts and designs. In the present review, an attempt is made to collect and structure all types of SOFC that exist today. Structural features of each type of SOFC have been described, and their advantages and disadvantages have been identified. A comparison of the designs showed that among the well-studied dual-chamber SOFC with oxygen-ion conducting electrolyte, the anode-supported design is the most suitable for operation at temperatures below 800 °C. Other SOFC types that are promising for low-temperature operation are SOFC with proton-conducting electrolyte and electrolyte-free fuel cells. However, these recently developed technologies are still far from commercialization and require further research and development.

The global population has increased over time, therefore the need for sufficient energy has risen. However, many countries depend on nonrenewable resources for daily usage. Nonrenewable resources take years to produce and sources are limited for generations to come. Apart from that, storing and energy distribution from nonrenewable energy production has caused environmental degradation over the years. Hence, many researchers have been actively participating in the development of energy storage devices for renewable resources using batteries. For this purpose, the lithium-ion battery is one of the best known storage devices due to its properties such as high power and high energy density in comparison with other conventional batteries. In addition, for the fabrication of Li-ion batteries, there are different types of cell designs including cylindrical, prismatic, and pouch cells. The development of Li-ion battery technology, the different widely used cathode and anode materials, and the benefits and drawbacks of each in relation to the most appropriate application were all thoroughly studied in this work. The electrochemical processes that underlie battery technologies were presented in detail and substantiated by current safety concerns regarding batteries. Furthermore, this review collected the most recent and current LIB recycling technologies and covered the three main LIB recycling technologies. The three recycling techniques—pyrometallurgical, hydrometallurgical, and direct recycling—have been the subject of intense research and development. The recovery of valuable metals is the primary goal of most recycling processes. The growth in the number of used LIBs creates a business opportunity to recover and recycle different battery parts as daily LIB consumption rises dramatically.

The global imperative to reduce greenhouse gas emissions and phase out fossil fuels has prompted hydrogen to emerge as a critical player in the transition to sustainable energy systems and eco-friendly transport solutions. This study endeavors to examine innovative technologies for hydrogen production and storage, with the objective of overcoming the obstacles that impede their widespread adoption. The integration of hydrogen with renewable energy sources is one of the methods that have been investigated. Specifically, the effectiveness of coupling hydrogen fuel cells with wind or solar power systems has been examined in order to ensure a reliable energy supply and improve grid stability. The results of this study present innovative methods for mass hydrogen production, including electrolysis of water and advanced techniques for extracting hydrogen from fossil fuels while minimizing environmental impact. Additionally, this study evaluates strategies for underground hydrogen storage, considering local geological conditions to optimize storage efficiency and safety. The findings indicate that salt caverns offer a secure and stable hydrogen containment system and have a high storage efficiency of up to 90%. The evaluation of depleted gas fields demonstrated promising results in terms of sealing integrity and storage efficiency (88%). The outcomes provide insights into the feasibility of large-scale hydrogen generation and storage, offering valuable guidance for future energy solutions dependent on hydrogen in diverse geographic contexts.

This review presents thermoelectric phenomena in copper chalcogenides substituted with sodium and lithium alkali metals. The results for other modern thermoelectric materials are presented for comparison. The results of the study of the crystal structure and phase transitions in the ternary systems Na-Cu-S and Li-Cu-S are presented. The main synthesis methods of nanocrystalline copper chalcogenides and its alloys are presented, as well as electrical, thermodynamic, thermal, and thermoelectric properties and practical application. The features of mixed electron–ionic conductors are discussed. In particular, in semiconductor superionic copper chalcogenides, the presence of a “liquid-like phase” inside a “solid” lattice interferes with the normal propagation of phonons; therefore, superionic copper chalcogenides have low lattice thermal conductivity, and this is a favorable factor for the formation of high thermoelectric efficiency in them.

Conventional solvents remain the most used media for lignocellulosic biomass valorization. However, these solvents exhibit many limitations and have a negative environmental impact. In the last decade, Deep Eutectic Solvents (DESs) have emerged as a multifaceted tool in biomass valorization, with a promising perspective in the application of lignocellulosic biomass valorization. DESs have gained attention in the last decade as an alternative solvent in biomass valorization and biorefinery processes due to their high efficiency; eco-friendliness; low cost; and numerous other advantages, such as recyclability, non-volatility, and stability. This paper discusses the latest research on the potential applications of DESs in the valorization of secondary lignocellulosic biomass.

Solar energy, which is widely acknowledged for its economic feasibility and sustainable nature, functions as a critical substitute for finite fossil fuels, effectively alleviating ecological consequences. The purpose of this study is to investigate the implementation of solar collectors as a means of harnessing the ample and unaltered solar radiation in Iran, specifically in locations situated within the solar belt. The incorporation of solar energy not only aids in the expansion of energy sources through diversification but also mitigates the rising expenses linked to fossil fuels. The preservation of natural resources, coupled with limited renewable energy options, further accentuates the importance of solar energy. The optimization of solar panel collector angles in photovoltaic systems assumes paramount importance for maximizing energy efficiency. This study, conducted in Yazd, Iran, utilized innovative mathematical and particle swarm optimization (PSO) models to assess ideal inclination angles. Results indicate peak solar energy absorption during June and July, contrasting with minimal absorption in January. The Klein model prescribes inclination angles based on γ values, while the PSO algorithm determines optimal slope and azimuth angles across various periods. Significant enhancements in energy generation, ranging from 23.24 to 25.02% across optimization models, were observed compared to a horizontal surface. These findings underscore the imperative of optimizing solar panel placement in urban settings to augment energy generation. Utilizing the optimal orientation for the photovoltaic power supply system can result in an annual reduction of 1169.6 kg of CO₂ emissions in the building, emphasizing the positive environmental impact achievable through strategic solar panel configurations.