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In recent years, there have been significant advancements in Al‐ion battery development, resulting in high voltage and capacity. Traditionally, only carbon‐based materials with layered structures and strong bonding capabilities can deliver superior performance. However, most other materials exhibited low discharge voltages of 1.4 V, especially in aqueous Al‐ion battery systems lacking anion intercalation. Thus, the development of high‐voltage cathode materials has become crucial. This study introduces 2D MoS2 as a high‐performance cathode for aqueous Al‐ion batteries. The material's interlayer structure enables the intercalation of AlCl4− anions, resulting in high‐voltage intercalation. The resulting battery achieved a high voltage of 1.8 V with a capacity of 750 mAh g−1, contributing to a high energy density of 890 Wh kg−1 and an impressive retention rate of ≈100% after 200 cycles. This research not only sheds light on the high‐voltage anion‐intercalation mechanism of MoS2 but also paves the way for the further development of advanced cathode materials in the field of Al‐ion batteries. By demonstrating the potential of using 2D MoS2 as a cathode material, this finding can lead to the development of more efficient and innovative energy storage technologies, ultimately contributing to a sustainable and green energy future. [ABSTRACT FROM AUTHOR]

In recent years, super-long and super-large diameter pipe piles have been gradually applied to the foundation in the Yellow River flood area. However, its bearing mechanism is not clear, especially the unclear bearing characteristics of the pile under the eccentric state, which limits its application and development. In this regard, this paper uses the method of combining field test and numerical simulation to analyze the bearing characteristics of super-long and super-large diameter pipe piles under different pile lengths, different pile diameters, different diameter-thickness ratios, and different offsets. Combined with the specific deviation form of the pipe pile, the calculation formula of the vertical ultimate bearing capacity of the super-long and super-long diameter pipe pile in the Yellow River flooding area under the influence of the construction effect is modified. The results show that when the length of the pipe pile changes, the vertical bearing capacity changes the most, and the vertical ultimate bearing capacity of the pipe pile increases linearly with the increase of the length of the pipe pile. When the wall thickness of the pipe pile increases, the vertical bearing capacity increases approximately linearly, but the reduction of the pile displacement decreases exponentially. The greater the deflection of the pipe pile, the smaller the vertical ultimate bearing capacity. When the deflection of the pipe pile is greater than 0.35°, the vertical ultimate bearing capacity decreases rapidly with the increase of the deflection. On the basis of the traditional formula, considering the deviation form of the pipe pile, the reduction coefficient of the bearing capacity correction formula of the super-long and super-large diameter pipe pile is proposed, and the correction formula is compared with the field example. It is proved that the formula can accurately calculate the bearing capacity of the superlong and super-large diameter pipe pile. The research results of this paper are of great significance to the application and promotion of super-long and super-large diameter pipe piles in the Yellow River flood area and the evaluation of vertical ultimate bearing capacity. At the same time, the research results of this paper can also provide a reference for the study of bearing characteristics of super-long and super-large diameter pipe piles in other foundations. [ABSTRACT FROM AUTHOR]

Direct hydrogen fuel cells are generally heavy and rigid systems based on metal or plastic materials, which are not suitable for various miniwatt and flexible devices. In this study, we have developed a lightweight and flexible fuel cell based on paper substrate embedded with an Al foil inside, which is used as an in-situ hydrogen source by reaction with an electrolyte solution during operation. Benefited from the inhibited hydroxyl transportation by the porous cellulose network, the vigorous Al corrosion reaction is well controlled even though strong alkaline electrolyte is adopted, so that the fuel cell can be discharged for more than 5 hours at 1 mA cm-2 (0.83 V) with only 3.5 mg Al foil. The corresponding faradaic and energy efficiencies are as high as 72% and 18.3%, respectively. The fuel cell flexibility is also quite good when facing different bending angles. Considering its moderate power output, this flexible paper-based hydrogen fuel cell is especially suitable for powering various miniwatt and flexible devices, such as wearable electronics, biosensors, RFID tags, etc. However, higher power can be obtained by suitable stacking of the fuel cell.

Since direct solar energy conversion is considered to be crucial for the development of a sustainable society, photocatalytic hydrogen evolution has been extensively studied during the past few years. Despite the recent progress in solar-driven hydrogen evolution, photoactivity is still limited due to fast recombination of charge carriers and scaled production is hard to proceed with. The rational design of photocatalysts with spatially separated charge carriers has been shown to be one of the promising strategies for better photocatalyst charge separation efficiency. The spatial separation of photoinduced electrons and holes, as well as the rapid migration of electrons from the bulk to the reaction surface, results in suppressed charge recombination, prolongs the lifetime of photogenerated charges and blocks the backward reaction. In this review, the basic concepts of photocatalytic hydrogen production with heterojunction systems are introduced. Then, the rational designs of heterojunction photocatalyst systems to enable spatially separated reaction sites are summarized and categorized based on their dimensions and architectures. Finally, the outlook and research directions are discussed towards the set target of solar to hydrogen conversion efficiency and industrial production. [ABSTRACT FROM AUTHOR]