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The electrosynthesis of valuable chemical feedstocks and fuels through the CO2 reduction reaction (CO2RR) provides a promising approach to solve the global warming problem and the energy crisis. Numerous studies have been devoted to developing electrocatalysts; however, few studies focus on Pb actives sites as well as the defect engineering of active sites. Herein, an O vacancy-rich PbCO3 electrocatalyst (O-PbCO3) derived Pb2(OH)2(CH3COO)2 precatalyst is reported. X-ray photoelectron spectroscopy (XPS) and electron paramagnetic resonance (EPR) results prove the existence of O vacancies while the X-ray absorption fine structure (XAFS) results reveal the distorted structure of the O-PbCO3. Electrochemical measurements of the O-PbCO3 sample exhibit a remarkable selectivity and activity towards formate of over 90% in a wide range of current densities of 50 to 400 mA cm−2. Further in situ surface-enhanced infrared absorption spectroscopy (SEIRAS) characterization indicates that the O vacancies can optimize the adsorption of the *HCOO intermediate for enhanced CO2RR performance. [ABSTRACT FROM AUTHOR]

Electrocatalytic water splitting, powered by clean energy sources, represents a sustainable method for hydrogen (H2) production. Although extensive research has concentrated on performance indicators like current density and faradaic efficiency, the widespread adoption of electrocatalytic water splitting encounters challenges primarily due to high cell voltages and electricity costs. These issues stem from the sluggish kinetics of the anodic oxygen evolution reaction (OER). Various efforts to replace sluggish OER with thermodynamically more favorable anodic reactions have been demonstrated as pathbreaking strategies for energy‐efficient H2 evolution. In this concept, we aim to comprehensively explore alternative electrochemical oxidation reactions combined with H2 evolution and propose insights for the future development of cost‐effective integrated electrolysis for H2 production. [ABSTRACT FROM AUTHOR]

Electrocatalytic carbon dioxide/carbon monoxide reduction reaction (CO(2)RR) has emerged as a prospective and appealing strategy to realize carbon neutrality for manufacturing sustainable chemical products. Developing highly active electrocatalysts and stable devices has been demonstrated as effective approach to enhance the conversion efficiency of CO(2)RR. In order to rationally design electrocatalysts and devices, a comprehensive understanding of the intrinsic structure evolution within catalysts and micro‐environment change around electrode interface, particularly under operation conditions, is indispensable. Synchrotron radiation has been recognized as a versatile characterization platform, garnering widespread attention owing to its high brightness, elevated flux, excellent directivity, strong polarization and exceptional stability. This review systematically introduces the applications of synchrotron radiation technologies classified by radiation sources with varying wavelengths in CO(2)RR. By virtue of in situ/operando synchrotron radiationanalytical techniques, we also summarize relevant dynamic evolution processes from electronic structure, atomic configuration, molecular adsorption, crystal lattice and devices, spanning scales from the angstrom to the micrometer. The merits and limitations of diverse synchrotron characterization techniques are summarized, and their applicable scenarios in CO(2)RR are further presented. On the basis of the state‐of‐the‐art fourth‐generation synchrotron facilities, a perspective for further deeper understanding of the CO(2)RR process using synchrotron radiation analytical techniques is proposed. [ABSTRACT FROM AUTHOR]

Objective To understand the prevalence and trend of hepatitis A and E in Yantai from 2011 to 2022, and to conduct serological research on hepatitis A and hepatitis E in the community population so as to provide data for effective prevention and control of two types of hepatitis. Methods The case-related information came from the monitoring data of China Disease Prevention and Control Information System. Descriptive epidemiological methods were used to analyze the prevalence of hepatitis A and hepatitis E in Yantai City from 2011 to 2022. Two areas in Yantai were selected bymulti-stage random cluster sampling method to carry out monitoring of hepatitis A and hepatitis E antibody levels in community populations. Enzyme linked immunosorbent assay (ELISA) was used to detect serum levels of anti-hepatitis A virus (HAV) and hepatitis E virus (HEV) antibodies. Results A total of 858 cases of hepatitis A and 3 145 cases of hepatitis E were reported from 2011 to 2022.The annual average incidence rate of hepatitis A was 1.01/100 000, and the incidence was sporadic throughout the year. The annual average incidence rate of hepatitis E was 3.72/100 000.The incidence was mainly in winter and spring. The reported cases of hepatitis A and hepatitis E were mainly concentrated in the northern coastal areas. 86.48% of the reported cases of hepatitis A are 25-69 years old, while 91.86% of the reported cases of hepatitis E were 35-79 years old. The composition of hepatitis A and hepatitis E was mainly men and farmers. A total of 600 blood samples were collected from healthy people, the overall seroprevalence of HAV IgM, HEV IgM, HAV IgG and HEV IgG were 1.83%, 85.67% and 32%, respectively. In terms of age, the positive rate of HAV IgM was the highest in 61-70 years old group (3.9%), HAV IgG positive rate in over 70 years old group was the highest, HEV IgM positive rate in 51-60 years old group was the highest (4.21%), and HEV IgG positive rate in over 70 years old group was the highest. Farmers had the highest positive rates of HAV IgG and HEV IgG, while students, household workers, and unemployed individuals have the highest positive rates of HAV IgM and HEV IgM. Farmers had the highest positive rates of HAV IgG (92.52%) and HEV IgG (46.26%), students had the highest positive rates of HAV IgM (2.78%) and housework and unemployed people had the highest positive rates of HAV IgM and HEV IgM (3.17%). Conclusion The incidence of hepatitis A and hepatitis E remained at a relatively high level in Yantai from 2011 to 2022, and the positive levels of HAV IgG and HEV IgG antibodies were relatively high. Further efforts need to be made to promote and intervene in key populations, especially men and farmers, to carry out relevant prevention and control measures and reduce infection rates. [ABSTRACT FROM AUTHOR]

MXenes have superior catalytic activities, because of their excellent electronic properties. In this work, the electronic properties, quantum capacitance, and photocatalytic activity of Pt-doped Zr2CO2 (Pt-VO-Zr2CO2) nanosheets under biaxial strain are investigated by first-principles calculations. Pt-VO-Zr2CO2 are all indirect semiconductors under compressive strain and are direct semiconductors under tensile strain except at 10%. The red shift of Zr-d and O-p orbitals in conduction bands results in the decrease of band gaps under compressive strain. Pt-VO-Zr2CO2 under strain except at −8% are cathode materials in an aqueous system, especially for Pt-VO-Zr2CO2 with +10% strain with the maximum storage charge. Pt-VO-Zr2CO2 under strain can reduce water at pH 0 and perform overall water splitting in a neutral environment. Pt-VO-Zr2CO2 nanosheets with a strain larger than +4% can reduce CO2 to all products, and tensile strain enhances CO2 photocatalysis. The N2 reduction capability of Pt-VO-Zr2CO2 reduces in a neutral environment. [ABSTRACT FROM AUTHOR]

Polar materials with spontaneous polarization (Ps) have emerged as highly promising photocatalysts for efficient photocatalytic H2 evolution owing to the Ps‐enhanced photogenerated carrier separation. However, traditional inorganic polar materials often suffer from limitations such as wide band gaps and poor carrier transport, which hinders their photocatalytic H2 evolution efficiency. Here, we rationally synthesized a series of isostructural two‐dimensional (2D) aromatic Dion–Jacobson (DJ) perovskites, namely (2‐(2‐Aminoethyl)pyridinium)PbI4 (2‐APDPI), (3‐(2‐Aminoethyl)pyridinium)PbI4 (3‐APDPI), and (4‐(2‐Aminoethyl)pyridinium)PbI4 (4‐APDPI), where 2‐APDPI and 4‐APDPI crystalize in polar space groups with piezoelectric constants (d33) of approximately 40 pm V−1 and 3‐APDPI adopts a centrosymmetric structure. Strikingly, owing to the Ps‐facilitated separation of photogenerated carriers, polar 2‐APDPI and 4‐APDPI exhibit a 3.9‐ and 2.8‐fold increase, respectively, in photocatalytic H2 evolution compared to the centrosymmetric 3‐APDPI. As a pioneering study, this work provides an efficient approach for exploring new polar photocatalysts and highlights their potential in promoting photocatalytic H2 evolution. [ABSTRACT FROM AUTHOR]

Enhancing the tunneling magneto-Seebeck (TMS) ratio and uncovering its underlying mechanism are greatly demanded in spin caloritronics. The magnitude and sign of the TMS effect depend on the type of atom and the stacking order of atoms at the interfaces. Herein, we demonstrate that TMS ratios can be effectively manipulated by altering heterogonous or homogeneous interface through decoration on the CoFeSi (001) surface inserted on the MgO insulating layers. The maximum TMS ratio of pure Co2/O termination is 4565% at 800 K. Notably, the TMS ratio of the FeSi/O termination has two peak values, of which the maximum could reach up to −3290% at 650 K. By comparing two different atom arrangements at the interface, we reveal that the sign and symbol of the TMS ratio can be controlled by the temperature and different atomic configurations at the Co2FeSi/MgO interface. Furthermore, the spin-Seebeck coefficient up to ∼150 µV/K is also possible when we select suitable terminations and temperatures. These findings will provide useful insights into how to control the sign and symbol of the TMS ratio and accordingly stimulate the development field of magneto-thermoelectric power and spin caloritronic devices based on the magneto-Seebeck effect in Heusler-based metallic multilayers. [ABSTRACT FROM AUTHOR]

The preparation method of superabsorbent resin and the advantages and disadvantages of each method are introduced. The influence of different modified materials on the water absorption and water retention performance of the superabsorbent resin was summarized, and the methods of increasing the specific surface area, molecular weight, the number of active groups, appropriate degree of neutralization and crosslinking degree were given to improve the water absorption and water retention ability. Then the applications of superabsorbent resin in environmental management, building materials and agriculture and forestry are summarized. The further improvement of the properties of the superabsorbent resin is prospected, and the development of low cost and degradable superabsorbent resin is still an urgent problem to be solved. [ABSTRACT FROM AUTHOR]

Calcium-silicon powder was used as raw material, calcium lignosulfonate-chitosan was added as organic binders, and silicon-calcium pellets were prepared by disc granulation technology. Different binders, calcium lignosulfonate, the effect of factors such as chitosan addition amount and drying temperature on the compressive properties and quick-dispersion properties of calcium silicate pellets were investigated, and the granulation process conditions were optimized. With the help of XRF, XRD, FTIR and other technologies, the raw materials and samples structure and properties were analyzed to explore the mechanism of agglomeration and granulation of silicon-calcium powder. The results show that the best molding and granulation conditions are 3.75% calcium lignosulfonate, 1.25% chitosan, and a drying temperature of 115 °C, the particles are closely agglomerated, and the average compressive strength is 34.4 N. The penetration of water molecules into the particles is accelerated, and the hydrostatic test results show that the samples could be completely disintegrated within 51 s. [ABSTRACT FROM AUTHOR]

Using first-principles calculations, we predict a new type of two-dimensional (2D) beryllium(Be)-decorated T-graphene named BeC2, where Be atoms are inserted into C–C bonds linking the carbon tetrarings of T-graphene. The band structure shows that BeC2 is metallic, thus, the possible phonon-mediated superconductivity is explored based on the Eliashberg equation. The calculated electron-phonon coupling (EPC) constant λ is up to 4.07, and the corresponding superconducting critical temperature (Tc) is 72.1 K, approaching the liquid nitrogen temperature. The reason for the high Tc is the strong EPC. And it is proved to be an anisotropic single-gap superconductor by analyzing the superconducting gap Δk of BeC2. The electronic susceptibility calculation shows strong nesting effect in BeC2. Since rare 2D superconductors show such a strong EPC constant λ which originates from the coupling between electrons in C–pz orbital and in-plane vibrations of Be and C atoms, the predicted BeC2 provides a new platform for investigating strong EPC 2D superconductor. [ABSTRACT FROM AUTHOR]

Proton exchange membrane (PEM) electrolysis holds great promise for green hydrogen production, but suffering from high loading of platinum-group metals (PGM) for large-scale deployment. Anchoring PGM-based materials on supports can not only improve the atomic utilization of active sites but also enhance the intrinsic activity. However, in practical PEM electrolysis, it is still challenging to mediate hydrogen adsorption/desorption pathways with high coverage of hydrogen intermediates over catalyst surface. Here, operando generated stable palladium (Pd) hydride nanoclusters anchored on tungsten carbide (WCx) supports were constructed for hydrogen evolution in PEM electrolysis. Under PEM operando conditions, hydrogen intercalation induces formation of Pd hydrides (PdHx) featuring weakened hydrogen binding energy (HBE), thus triggering reverse hydrogen spillover from WCx (strong HBE) supports to PdHx sites, which have been evidenced by operando characterizations, electrochemical results and theoretical studies. This PdHx-WCx material can be directly utilized as cathode electrocatalysts in PEM electrolysis with ultralow Pd loading of 0.022 mg cm-2, delivering the current density of 1 A cm-2 at the cell voltage of ~1.66 V and continuously running for 200 hours without obvious degradation. This innovative strategy via tuning the operando characteristics to mediate reverse hydrogen spillover provide new insights for designing high-performance supported PGM-based electrocatalysts., (© 2024 Wiley‐VCH GmbH.)

Inefficient active site utilization of oxygen evolution reaction (OER) catalysts have limited the energy efficiency of proton exchange membrane (PEM) water electrolysis. Here, an atomic grid structure is demonstrated composed of high-density Ir sites (≈10 atoms per nm 2 ) on reactive MnO 2-x support which mediates oxygen coverage-enhanced OER process. Experimental characterizations verify the low-valent Mn species with decreased oxygen coordination in MnO 2-x exert a pivotal impact in the enriched oxygen coverage on the surface during OER process, and the distributed Ir atomic grids, where highly electrophilic Ir─O (II-δ)- bonds proceed rapidly, render intense nucleophilic attack of oxygen radicals. Thereby, this metal-support cooperation achieves ultra-low overpotentials of 166 mV at 10 mA cm -2 and 283 mV at 500 mA cm -2 , together with a striking mass activity which is 380 times higher than commercial IrO 2 at 1.53 V. Moreover, its high OER performance also markedly surpasses the commercial Ir black catalyst in PEM electrolyzers with long-term stability., (© 2024 Wiley‐VCH GmbH.)