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As renewable energy advances, the demand for improved battery solutions becomes increasingly urgent. Zinc–air batteries have emerged as leading contenders, offering remarkable energy density coupled with cost efficiency. However, challenges such as dendritic growth, corrosion, and the accumulation of byproducts within the zinc anode hinder their optimal performance and longevity. Functional gel electrolytes have garnered significant attention, as they not only address current issues with the Zn anode but also mitigate the risk of electrolyte leakage and enhance adaptability in batteries. This Review begins by outlining the design of functional gel electrolytes tailored to adeptly curb zinc anode dendrite formation and corrosion. Additionally, it explores the advantages and disadvantages of different types of gel electrolytes for stabilizing the Zn anode, along with prospects for designing novel gel electrolytes. Consequently, this sets a solid groundwork for the continual evolution of battery technology.

The cloud-edge-end architecture is suitable for many essential scenarios, such as 5G, the Internet of Things (IoT), and mobile edge computing. Under this architecture, cross-domain and cross-layer data sharing is commonly in need. Considering cross-domain data sharing under the zero-trust model, where each entity does not trust the others, existing solutions have certain problems regarding security, fairness, scalability, and efficiency. Aiming at solving these issues, we conduct the following research. First, a new plaintext checkable encryption scheme is constructed, which can be used on lightweight IoT devices to verify the ciphertext validity sent by a data owner. Second, we propose a new multi-domain cloud-edge-end architecture based on sharding blockchains and design a cross-domain data sharing scheme under the partial trust model to achieve security, scalability, and high performance. Third, a cross-domain data sharing scheme under the zero trust model is further designed, which can ensure the fairness of both parties in data sharing. Fourth, we give a formal security definition and analysis of cross-domain data sharing. Fifth, we conduct a detailed theoretical analysis of the protocol and give an in-depth functional test and performance test, including the throughput and latency of data sharing policy registration and execution.

Despite the unsettled mechanism of electricity generation from the continuous flow of liquids on a surface, the charge-discharge theory has been widely accepted for alternating current (AC) generation from a moving droplet. It has been recently extended to rationalize direct current (DC) generation across a droplet moving between two different materials. By designing a reconfigurable contact between a metal wire and a water droplet moving on graphene, we show that the charge-discharge theory cannot explain the reversal of current when water-metal interfaces switch from dynamic to static. All experiments can be described after we distinguish a dynamic from a static interface and generalize the photovoltaic-like effect to all dynamic junctions: excited electrons and holes in a moving interface will be separated and swept under the built-in electrical field, leading to a DC response. This generalized theory will lead to an understanding and the design of efficient electricity generation based on interfacial charge transfer.

A facile hydrothermal method has been developed for the synthesis of nanosized Cu–CeO2composites with various Cu contents. The obtained catalysts, with a Cu/CeO2atomic ratio in the range of 0–40%, were characterized as to their structure, morphology, and redox features by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, N2physisorption, and temperature programmed reduction with hydrogen. The experimental results show that the particles are highly crystalline CeO2nanopowders of 5–8 nm primary particle size and the Cu nanoparticles indeed coexist with the CeO2nanoparticles (cubic fluorite CeO2). The influence of Cu contents on their catalytic performance for CO oxidation was also studied. As for the catalytic reactivity, nanosized Cu–CeO2composites have a higher catalytic activity than CeO2in CO oxidation. It is ascribed to the effect between the cycle transition of Ce4+/Ce3+, oxygen vacancies and surface area, which are induced by copper. The catalytic activity of the Cu–CeO2composites exhibits Cu content dependence where the best catalytic activity occurs at a Cu/CeO2atomic ratio of 30%. In addition, nanosized Cu–CeO2composites also show high catalytic activity for selective oxidation of CO in excess H2at relatively low temperature.

Developing efficient and stable oxygen evolution reaction (OER) catalysts that can work well at high current densities for seawater electrolysis is desirable but remains a significant challenge. Here a novel and scalable strategy is developed to synthesize partially amorphous boron-modified cobalt iron layered double hydroxides (B-Co2Fe LDH). Benefiting from enhanced electronic kinetics and abundant active sites, this hierarchical nanosheet-nanoflake-structured B-Co2Fe LDH catalyst shows superb OER catalytic activity, requiring overpotentials of 205 and 246 mV to drive current densities of 10 and 100 mA cm−2, respectively, in 1 M KOH, along with a small Tafel slope of 39.2 mV dec−1. Its partial amorphousness feature leads to enhanced stability and corrosion resistance, which help the B-Co2Fe LDH catalyst to work well in the critical seawater condition. It requires overpotentials of 310 and 376 mV to drive current densities of 100 and 500 mA cm−2, respectively, in 1 M KOH seawater and can work continuously for 100 h without producing any hypochlorite. This work can enable the development of LDH catalysts for highly selective seawater oxidation using a general approach.

GAS is among the most common human pathogens and causes a wide variety of diseases, likely more than any other microorganism. The diverse clinical manifestations of GAS may be attributable to its large repertoire of virulence factors that are selectively and synergistically involved in streptococcal pathogenesis. To date, GAS vaccines have not been successful due to multiple serotypes and postinfection sequelae associated with autoimmunity. In this study, five conserved virulence factors that are involved in GAS pathogenesis were used as a combined vaccine. Intranasal immunization with this vaccine induced humoral and cellular immune responses across GAS serotypes and protected against mucosal, systemic, and skin infections. The significance of this work is to demonstrate that the efficacy of GAS vaccines can be achieved by including multiple nonredundant critical virulence factors and inducing local and systemic immunity. The strategy also provides valuable insights for vaccine development against other pathogens.

The g-C3N4/SnO2composites were synthesized via a simple two-step method. A sensor based on 10 wt% g-C3N4/SnO2composites shows excellent gas-sensing properties toward isopropanol compared with other sensors based on different mass ratio. The results indicate its potential application in isopropanol detection.The 10 wt% g-C3N4/SnO2composites were prepared via a facile two-step method and improved gas response of 61.63 toward 100 ppm isopraopanol gas. The detection limit as low as 1 ppm with the gas response of 4.61. The results demenstrate the potential of using g-C3N4/SnO2for isopropanol gas detection.

A facile hydrothermal method is used to prepare Pt‐functionalized nanoporous TiO2nanoparticles. These are used as gas‐sensing material in sensors, fabricated according to the indirect heating method. Gas‐sensing performance of the sensors is investigated by testing their gas response to acetone, which exhibits favorable selectivity, good gas response value, fast response/recovery time, low detection concentration and good long‐term stability to acetone. Gas response βwas defined as the ratio of Ra/Rg, where Raand Rgare the resistance values of gas sensor exposed in air and objective gas, respectively. Among all these as‐prepared gas sensors, the 0.5% Pt‐functionalized TiO2based gas sensor shows the highest gas response value of 29.51–200 ppm acetone at 300 °C, and the gas response value is 5.2 times higher than that (5.67) of pure TiO2based gas sensor. It also has excellent selectivity to acetone when comparing with toluene, n‐butanol, isopropanol, ethanol, and methanol. The large specific surface area (168.101 m2g−1) provides enough contacting interface between gas and the as‐prepared materials, then the gas molecules could be broken into CO2and H2O by the active adsorbed oxygen species. The present results of the Pt‐functionalized TiO2based gas sensors illustrates their potential application in detecting acetone. A nanoporous 0.5%Pt‐functionalized TiO2sample shows enhanced ability to capture more oxygen molecules and provides more active reaction sites on the interface to benefit the reaction between gas molecules and material. It exhibits excellent gas‐sensing performances, like high response value, fast response/recovery time, good repeatability, and reproducibility toward acetone gas.