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The offshore crude oil spill has caused serious environmental damage and affected the balance of the ecosystem. Due to the high viscosity and poor fluidity of crude oil, conventional adsorbents cannot effectively remove it. The heat converted from solar energy can reduce the viscosity of the crude oil, improved its fluidity, allowing it to be adsorbed by a porous material and then recycle, it is considered an effective approach. Herein, we have designed a melamine composite sponge decorated with Fe3O4 and modified by PDMS (MS@Fe3O4-PDMS) with good photothermal conversion performance, which can recover viscous crude oil with the assistance of solar energy. The surface temperature of MS@Fe3O4-PDMS can reach around 88.0 ℃ under the light intensity of 1 kW·m− 2, effectively heating crude oil and accelerating its absorption. In the continuous crude oil recovery experiment, the absorption rate of MS@Fe3O4-PDMS reached 52.46 kg·m− 2·h− 1. In addition, the composite sponge has good processability, facile preparation method, and practical application potential. [ABSTRACT FROM AUTHOR]

Owing to their highly predictable porous structures, facile synthesis, and the presence of functional open metal sites, metal–organic frameworks (MOFs) are extensively employed in various fields, including energy storage, catalysis, adsorption, and separation. Nevertheless, the limited hydrolytic stability exhibited by numerous MOFs poses a significant challenge to their practical application. In the present study, we present the synthesis and characterization of a uranyl organic framework (TCPP‐U1) with a highly porous structure, which is constructed by assembling cobalt, uranyl, and the porphyrin ligand 5,10,15,20‐tetra(4‐carboxyphenyl)porphyrin (TCPP). However, TCPP‐U1 demonstrates poor hydrolytic stability when exposed to water (the structure can be destroyed even after 2 min of exposure to water), greatly impeding its potential applications that would benefit from its high surface area. To address this limitation, we developed a hybrid composite by incorporating acid‐treated multi‐walled carbon nanotubes (CNTs) into the TCPP‐U1 framework via a solvothermal method designated as CNTs@TCPP‐U1. Remarkably, the obtained CNTs@TCPP‐U1 composite possesses an identical crystal structure and morphology to the original TCPP‐U1 yet exhibits significant enhancements in hydrolytic stability (the structure remains stable even after 3 days of immersion in water). Furthermore, CNTs@TCPP‐U1 demonstrates a significant photocatalytic effect on the degradation of tetracycline hydrochloride in aqueous solutions. The reaction rate constant (k) for the pseudo‐first‐order kinetic model is 0.0059 min−1. Our findings present a novel perspective for enhancing the stability and expanding the performance of MOFs materials. [ABSTRACT FROM AUTHOR]

Herein, Cu3P was used as a co-catalyst to improve the separation efficiency of photogenerated carriers in WSe2 photocatalysts. The metallic nature of Cu3P and its noble metal-like properties make it an affordable and efficient co-catalyst. The experimental results revealed that the photocatalytic activity of the WSe2/Cu3P (WP) sample was significantly higher under visible light with an average hydrogen evolution rate (HER) of 616.50 μmol h−1 g−1 and a quantum yield of 23.75%. In contrast, the average HER of the pure WSe2 sample was only 298.46 μmol h−1 g−1. The preparation parameters were optimized by a single-factor test. The optimal preparation parameters were as follows. The loading of Cu3P was 8%, and the calcination time and temperature were 2.0 h and 300 °C, respectively. An innovative exploration of the photocatalytic memory effect of WP photocatalyst was carried out. The analysis of the experimental results displayed that the HER of the WP photocatalyst under dark conditions reached 418.50 μmol h−1 g−1 after 5.0 h post-illumination. [ABSTRACT FROM AUTHOR]

Solar‐driven interfacial evaporation is one of the means to effectively alleviate the global shortage of freshwater resources without the need for additional energy supply. Although the emergence of various evaporators has improved the evaporation rate and efficiency, it still needs further efforts in terms of improving space utilization, reducing material waste, and enhancing salt resistance. Herein, a 3D bridge evaporator H1.68MoO3/MS (MS, melamine sponge) is designed, where H1.68MoO3 and MS endow the evaporator with high light absorption in the whole wavelength range and excellent water transport capability, respectively. The support of expanded polystyrene realizes the self‐floating of the device, and the evaporation interface is arched upward and exposed to the air in a bridge shape, effectively improving the space volume utilization rate, reducing material consumption and reducing the heat loss during the evaporation process. Under the sunlight intensity of 1 kW m−2, the evaporator achieves an evaporation rate of 2.75 kg m−2 h−1 and an evaporation efficiency of 167.0%, meanwhile showing excellent resistance to salt deposition and ability to remove heavy metals and dyes (removal efficiency over 99%). In addition, the evaporation performance of the evaporator remains stable in the evaporation experiment lasting for 10 days, showing good long‐term usability. [ABSTRACT FROM AUTHOR]

The construction of heterojunction photocatalysts is an effective strategy to improve photocatalytic activity. Inspiringly, this is studied by the successful fabrication of new composites of a robust Zr-MOF and low-cost g-C3N4via a simple method of mechanical grinding followed by low-temperature heating. The synthesized composites exhibit characteristics of wide-range visible-light absorption, good long-term stability and significant photocatalytic hydrogen production. The optimal H2 production rate of the Zr-MOF/g-C3N4 (5.0 wt%) heterojunction was 1.252 mmol h−1 g−1, which was 41.7 and 15.7 times higher than that of pure Zr-MOF and g-C3N4, respectively. The Z-scheme charge transfer mechanism in Zr-MOF/g-C3N4 effectively improves charge separation and maintains its high redox ability, thus greatly enhancing photocatalytic hydrogen production activity. This study presents the rational fabrication of heterojunctions for photocatalytic applications and also provides new high-performance and low-cost MOF/g-C3N4 photocatalysts for H2 production. [ABSTRACT FROM AUTHOR]

The oxygen reduction reaction (ORR) plays a pivotal role in electrochemical energy conversion and chemical production. Two‐electron (2e−) charge transfer for oxygen reduction is considered a promising method for the on‐site production of hydrogen peroxide (H2O2), which requires electrocatalysts with high H2O2 selectivity and ORR activity. Noble metal alloys (e.g., Pt‐Hg and Pd‐Hg) have been prevalent materials of choice due to their desirable intrinsic activity, but their scarcity and high cost seriously hinder their widespread application in practice. Self‐doped heteroatomic carbon‐based electrocatalysts, derived from abundant and inexpensive biomass, have emerged as attractive candidates for on‐site H2O2 production. This review summarizes the fundamentals and recent advances in H2O2 production via 2e− ORR, including basic catalytic mechanisms, the influence of electrolyte pH and porous structure of catalysts, selectivity assessment methods, determination of the cumulative H2O2 concentration, development of biomass‐derived carbon‐based catalyst, and electrochemical device designs. Current challenges and proposed opportunities are also presented with an emphasis on large‐scale electrochemical H2O2 synthesis. [ABSTRACT FROM AUTHOR]

Vibration damping fastener is an important means for vibration and noise reduction in urban rail transit. At present, a common type of double-layer nonlinear vibration damping fastener has such problems as large consumables and high installation height. In this paper, a design scheme for a double-layer nonlinear vibration damping fastener is provided by means of structural design, simulation analysis and indoor test, which can effectively overcome the defects existing in a certain type of fastener. After indoor drop hammer test, the vibration reduction effect reaches 8. 9 dB. The Fatigue test indicates that the vertical stiffness of the system is 17 kN/mm, which meets the requirements of medium vibration damping stiffness. The traffic safety analysis shows that the derailment coefficient is low and meets the safety requirements. It is thus ensured that the fastener satisfies the requirements of medium vibration reduction fasteners and can be used for medium vibration reduction tracks of urban rail transit. [ABSTRACT FROM AUTHOR]