材料导报:能源(英文)最新文献

Recently, aqueous rechargeable batteries have played an essential role in developing renewable energy due to the merits of low cost, high security, and high energy density. Among various aqueous-based batteries, aqueous magnesium ion batteries (AMIBs) have rich reserves and high theoretical specific capacity (3833 mAh cm⁻³). However, for future industrialization, AMIBs still face many scientific issues to be solved, such as the slow diffusion of magnesium ions in the material structure, the desolvation penalty at electrode-electrolyte interfaces, the cost of water-in-salt electrolyte, the low voltage of traditional aqueous electrolyte, etc. And yet a comprehensive summary of the components of AMIBs is lacking in the research community. This review mainly introduces the exploration and development of AMIB systems and related components. We conduct an in-depth study of the cathode materials appropriate for magnesium ion batteries from their crystal structures, focusing primarily on layered structures, spinel structures, tunnel structures, and three-dimensional framework structures. We also investigate the anode materials, ranging from inorganic materials to organic materials, as well as the electrolyte materials (from the traditional electrolyte to water-in-salt electrolyte). Finally, some perspectives on ensuing optimization design for future research efforts in the AMIBs field are summarized.

Ammonia (NH₃) is a cornerstone widely used in the modern agriculture and industry, the annual global production gradually increases to almost 200 million tons. Nearly 80% of the produced NH₃ is used in the fertilizer industry and is essential for the development of global agriculture and consequently for maintaining population growth. Furthermore, NH₃ can power hydrogen (H₂) fueled devices, such as H₂ fuel cells (FC), to use the interconversion between chemical energy and electric energy of nitrogen (N₂) cycle, which can effectively alleviate the intermittent problems of renewable energy. However, the problems faced by NH₃ in storage and release still restrict its development. Herein, this review introduces the latest research and development of electrochemical NH₃ synthesis and direct NH₃ FC, as well as outlines the technical challenges, possible improvement measures and development perspectives. N₂ reduction reaction (NRR) and nitrate reduction reaction (NO₃⁻RR) are two potential approaches for electrochemical NH₃ synthesis. However, the existing research foundation still faces challenges in achieving high selectivity and efficiency. Direct NH₃ FC are easy to transport and are expected to be widely used in mobile energy consuming equipment, but also limited by the lack of highly active and stable NH₃ oxidation electrocatalysts. The perspectives of ammonia fuel cells as an alternative green energy are discussed.

Polysulfide absorption in a micropore-rich structure has been reported to be capable of efficiently confining the shuttle effect for high-performance lithium-sulfur (Li–S) batteries. Here, a labyrinth maze-like spherical honeycomb-like carbon with micropore-rich structure was synthesized, which is employed as a template host material of sulfur to study the shuttle effects. The results strongly confirm that a diffusion controlled process rather than an absorption resulted surface-controlled process occurs in an even micropore-rich cathode but still greatly inhibits the shuttle effect. Thus, the battery achieves a high initial discharge specific capacity of 1120 mAh g⁻¹ at 0.25 C and super cycling stability for 1635 cycles with only 0.035% capacity decay per cycle with 100% Coulombic efficiency. We would like to propose a new mechanism for shuttle effect inhibition in micropores. In terms of the diffusion control process in microporous paths of a labyrinth maze structure, polysulfides experience a long travel to realize continuous reductions of sulfur and polysulfides until formation of the final solid product. This efficiently prevents the polysulfides escaping to electrolyte. The labyrinth maze-like honeycomb structure also offers fast electron transfer and enhanced mass transport as well as robust mechanical strength retaining intact structure for long cycle life. This work sheds lights on new fundamental insights behind the shuttle effects with universal significance while demonstrating prominent merits of a robust labyrinth maze-like structure in high performance cathode for high-performance Li–S batteries.

The orientation construction of S-doped porous carbon fibers (SPCFs) is realized by the facile template-directed methodology using asphalt powder as carbon source. The unique fiber-like morphology without destruction can be well duplicated from the template by the developed methodology. MgSO₄ fibers serve as both templates and S dopant, realizing the in-situ S doping into carbon frameworks. The effects of different reaction temperatures on the yield and S doping level of SPCFs are investigated. The S doping can not only significantly enhance the electrical conductivity, but also introduce more defects or disorders. As anode material for lithium ion batteries (LIBs), SPCFs electrode delivers better rate capability than undoped PCFs. And the capacity of SPCFs electrode retains around 90% after 300 cycles at 2 A g⁻¹, exhibiting good cycling stability. As the electrocatalysts for fuel cells, the onset potentials of SPCFs obtained at 800 and 900 °C are concentrated at 0.863 V, and the higher kinetic current densities at 0.4 V of them are larger than that of PCFs, demonstrating the superior electrocatalytic performance. Due to the synergistic effect of abundant pore channels and S doping, SPCFs electrode exhibits superior electrochemical performances as anode for LIBs and elecctrocatalyst for fuel cells, respectively. Additionally, the oriented conversion of asphalt powder into high-performance electrode material in this work provides a new way for the high value application of asphalt.

Solid oxide fuel cells (SOFCs) and electrolysis cells (SOECs) are promising energy conversion devices, on whose basis green hydrogen energy technologies can be developed to support the transition to a carbon-free future. As compared with oxygen-conducting cells, the operational temperatures of protonic ceramic fuel cells (PCFCs) and electrolysis cells (PCECs) can be reduced by several hundreds of degrees (down to low- and intermediate-temperature ranges of 400–700 °C) while maintaining high performance and efficiency. This is due to the distinctive characteristics of charge carriers for proton-conducting electrolytes. However, despite achieving outstanding lab-scale performance, the prospects for industrial scaling of PCFCs and PCECs remain hazy, at least in the near future, in contrast to commercially available SOFCs and SOECs. In this review, we reveal the reasons for the delayed technological development, which need to be addressed in order to transfer fundamental findings into industrial processes. Possible solutions to the identified problems are also highlighted.

At present, petroleum remains the single largest global source of nearly all transportation fuel and the main source of industrial chemicals. But the legislative demand for cleaner fuel in automobile worldwide has forced scientists to develop and adopt new technologies to reduce the amount of sulphur in fuel. In this study, a Co–Mo catalyst supported on zeolite synthesized from local clay was developed and tested in hydrodesulphurization reactions, using Bonny light crude oil feed. The Co–Mo was incorporated into the zeolite by wet impregnation method and its activity was evaluated in a batch reactor. The catalyst was characterized and the efficiency was investigated in terms of product distribution and reaction conditions. With a rise in the temperature, the sulphur in the crude oil gets released into the liquid and gas effluents. In the case of gas effluents, the removal of sulphur depends on the reaction temperature, while in the liquid products, the removal of sulphur lies on the reaction time rather than the reaction temperature. The use of this catalyst results in significant upgraded and enhanced oil production with an environmentally friendly fuel, which therefore recommended as an alternative to conventional industrial catalysts.

Powered by electricity from renewable energies, electrochemical reduction of CO₂ could not only efficiently alleviate the excess emission of CO₂, but also produce many kinds of valuable chemical feedstocks. Among various catalysts, single atom catalysts (SACs) have attracted much attention due to their high atom utilization efficiency and expressive catalytic performances. Additionally, SACs serve as an ideal platform for the investigation of complex reaction pathways and mechanisms thanks to their explicit active sites. In this review, the possible reaction pathways for the generation of various products (mainly C1 products for SACs) were firstly summarized. Then, recent progress of SACs for electrochemical reduction of CO₂ was discussed in aspect of different central metal sites. As the most popular and efficient coordination modulation strategy, introducing heteroatom was then reviewed. Moreover, as an extension of SACs, the development of dual atom catalysts was also briefly discussed. At last, some issues and challenges regarding the SACs for CO₂ reduction reaction (CO₂RR) were listed, followed by corresponding suggestions.

Electrochemical water splitting powered by renewables-generated electricity represents a promising approach for green hydrogen production. However, the sluggish kinetics for the hydrogen evolution reaction (HER) under an alkaline medium causes a massive amount of energy losses, hindering large-scale production. Exploring efficient and low-cost catalyst candidates for large-scale H₂ generation becomes a crucial demand. Single-atom catalysts (SACs) demonstrate great promise for enabling efficient alkaline HER catalysis at maximum atom utilization efficiency. In this review, we provide a comprehensive overview of the recent progress in SACs for the HER application in alkaline environments. The fundamentals of alkaline HER are first introduced, followed by a justification of the need to develop SACs. The rational design of the SACs including the inherent element property, coordination environment, SAC morphology, and SAC mass loading are highlighted. To facilitate the development of SACs for alkaline HER, we further propose the remaining challenges and perspectives in this research field.