Ammonia borane (AB) is a promising hydrogen storage medium widely used for hydrogen generation, but its slow hydrolysis kinetics limits its applications. Medium/high-entropy materials (M/HEMs) have emerged as efficient catalysts due to their complementary elemental and structural properties. We developed a deposition in-situ reduction (D-ISR) approach for the rapid synthesis of single-phase medium/high-entropy oxides (M/HEOs) at room temperature, along with establishing general criteria for M/HEOs synthesis based on component properties. Deposition facilitates the incorporation of active elements (Ti/Zr/V/Cr/Nb), which significantly enhance the enthalpy-driven force of the dynamic oxidation (DO) process via an "active element coordination" strategy, thereby overcoming low-temperature solid solubility limitations. Nine-component HEOs and large-scale experiments confirm the universality and mass-production potential of the D-ISR approach. CoCuNiTi-O/AC synthesized via this strategy exhibits pronounced crystal distortion and disorder (Co-O coordination number = 10.2), enhancing the Co-O coordination environment and mitigating Ostwald ripening. This leads to high activity and significantly enhanced structural stability, achieving a turnover frequency of 236.6 min-1 for ammonia borane hydrolysis, 15 times higher than Co-O/AC and surpassing the most non-noble catalysts. These observations highlight an efficient M/HEOs synthesis methodology that advances M/HEMs applications in nanoenergy. (c) 2025 Science Press and Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. and Science Press. All rights are reserved, including those for text and data mining, AI training, and similar technologies.

Magnesium (Mg)-based materials exhibit higher hydrogen-storage density among solid-state hydrogen-storage materials (HSMs). Highly reliable hydrolysis can be achieved using them for hydrogen production. They can also achieve the integration of hydrogen production and storage via the regeneration. Furthermore, rechargeable magnesium batteries (RMBs), which possess desirable qualities that exhibit immense potential in addressing challenges related to lithium resource scarcity. However, limitations like high desorption temperature, poor cycle life, low hydrolysis rate, and propensity for passivation layer on Mg anodes, hinder their large-scale use as promising energy storage materials (ESMs). Herein, the review offers a comprehensive summary and analysis of the latest research in Mg-based materials for hydrogen storage, production, regeneration and RMBs. We summarize the impact of different methodologies on the thermodynamic and kinetic properties of MgH2. In particular, we thoroughly investigate the commonly used methods for enhancing the hydrolysis efficiency of Mg/MgH2. The currently research status on the regeneration of borohydrides by Mg-based materials is also summarized. In addition, the advantages and disadvantages of utilizing Mg as anode material in RMBs are also evaluated. This review aims to provide a fundamental insight of Mg-based materials and technologies and offer new strategies for promoting the sustainable development of advanced Mg-based materials.

The high hydrogen desorption density (19.6 wt mol_H_2 molCoO−1 min−1 at 298 K). Further studies indicated that the incorporation of Cu2O alters the electronic distribution of the surface of catalysts, introducing more oxygen vacancies and increasing the pyridinic nitrogen content. The increased oxygen vacancies effectively enhanced the adsorption and activation ability of active sites for reactants (H2O and AB), while the targeting effect of pyridinic nitrogen enhances the dispersion of the catalyst. Theoretical analysis reveals that CoO plays a key role in the dissociation of H2O, while minor doping with Cu2O substantially reduces the dissociation energy barrier of AB. This research provides a novel strategy for the design and efficient preparation of AB hydrolysis catalysts for efficient hydrogen production.

Heterostructured multicomponent catalysts can be developed to exploit their unique interfacial effects for enhancing their catalytic activities by optimizing their electronic structures. However, the precise fabrication of heterostructures remains challenging owing to the complex interfacial properties and compatibility problems between the different materials. To address these challenges, the carbothermal shock (CTS) method was employed to produce robust heterostructured CoO-MoO2 catalysts supported on C (CoO-MoO2@C) with the aid of extensive π-π electron conjugation of the organic components. Co-based ZIF-67, which is a typical metal-organic framework, and molybdenum acetylacetonate were used as Co and Mo sources, respectively. The strong coupling between the π-electrons of the organic ligands and ultrafast Joule heating during CTS improved the interfacial compatibility between the Co and Mo oxides, leading to a significantly enhanced catalytic activity. The heterostructured CoO-MoO2@C catalyst exhibited a turnover frequency of 55.4 min-1 in NH3BH3 hydrolysis for H2 production, displaying an improvement of 85.9% compared with that of the single-component CoO catalyst produced under equivalent conditions. Notably, the activation energy of CoO-MoO2@C was 29.3 kJ mol-1. In addition, we proposed a novel descriptor, i.e., the "activity-activation energy quotient", to comprehensively evaluate the energy efficiencies of catalysts in designing a low-energy-consumption catalyst. CoO-MoO2@C exhibited an activity-activation energy quotient of 1.89 min-1 kJ-1 mol, surpassing those of most reported Co-Mo-based catalysts. In summary, this study offers an advanced strategy for the structural design and precise fabrication of efficient non-noble-metal catalysts.

Hydrolysis is regarded as a safe, efficient and adorable approach to generate hydrogen (H2) from magnesium (Mg) or Mg-based materials. In this work, biochar (BC) and ferric oxide (Fe2O3) coated biochar (magnetic biochar: MBC) were synthesized and applied along with Mg as catalysts for an enhanced H2 generation. The Mg-Xwt %Y (X = 1.0, 3.0, 5.0, 10.0, 15.0 and Y = BC, MBC) composites were prepared via ball milling and employed to investigate their hydrolysis performance through kinetics in seawater. Among employed dosages, 10.0 wt% contents exhibited the best hydrolysis performance. Mg-10.0 wt%BC and Mg-10.0 wt%MBC composites after 1 h ball milling generated 820.03 and 828.02 mL/g (conversion yields of 89.03% and 89.99%) H2 in 40 and 10 min, respectively. Further, 10.0 wt% of BC and MBC decreased the hydrolysis kinetic energy of Mg from 63.9 to 41.07 and 17.16 kJ/mol, respectively. MBC has better catalytic effects for Mg hydrolysis compared with those by BC could be due to relatively more functional groups, providing more channels for water molecules to interact with Mg resulting in subsequent enhanced hydrolysis. Hence, MBC increased the reactivity and galvanic corrosion of Mg as well as prevented the formation of passive layer of magnesium hydroxide (Mg(OH)2) on fresh surface of Mg. The performance of MBC-supported Mg in hydrolysis process is anticipated to be essential for the creation of environmentally-friendly portable H2 generators, the use of clean generation of H2 energy and the reduction of environmentally adverse emissions.

Onsite hydrogen generation by sodium borohydride hydrolysis resolves hydrogen energy supply system challenges. However, the spent-NaBH4 regeneration is still a problem in the closed loop of this irreversible reaction. As the by-product is the key to the problem, NaB(OH)4 is regarded as not the boron source but the hydrogen source of NaBH4 regeneration. Therefore, in this study, inexpensive Al metal and NaB(OH)4 are ball milled under argon to regenerate NaBH4 without additional hydrogen input. However, the ball-milling reaction is hindered by the flexible Al and impact oxide layer, and the NaBH4 yield is only approximately 22 %. Therefore, a brittle intermetallic compound Mg2Al3 is reacted with NaB(OH)4 by ball milling, achieving a NaBH4 yield of over 42 %. The mechanism study shows that the brittleness of the raw material plays an important role in promoting the ball-milling reaction. This study achieves NaBH4 regeneration using only Al as the reducing agent and provides a promising method to promote the mechanochemical regeneration of NaBH4.

Given the environmental pollution and thermal risks of lithium-ion batteries, it is necessary to recycle and evaluate the safety of spent lithium-ion batteries. Here, lithium tin alloys (LixSny) were prepared via mechanical alloying to simulate the tin anode materials at different lithium-embedded states. Among them, the Li22Sn5 alloy showed the optimum hydrolysis performance, releasing 351 mL g-1 hydrogen in 10 s at 293 K. The safety evaluation was carried out based on hydrolysis performance, maximum adiabatic temperature rise, and other parameters. The Li22Sn5 alloy required 738.8 mL of water to cool down to 303 K. Moreover, the reaction rates can be precisely controlled by tailoring the solution components, which effectively promoted the security and controllability for practical application. In addition, the hydrogen production of Li22Sn5 sample after hydrogenation increased to 624 mL g-1, even at a subzero temperature of 243 K, 510 mL g-1 hydrogen can be generated within 30 s. This study provides a new idea for the safety evaluation and recycling of tin anode materials in spent lithium-ion batteries. (c) 2023 Elsevier B.V. All rights reserved.

Metal borohydrides have high theoretical hydrogen production/storage densities (> 10 wt%) and offer an efficient real-time hydrogen supply for small and medium-sized mobile/portable electronics through catalytic hydrolysis under mild conditions. They are also suitable for large-scale applications. However, their practical applications are limited because of by their complex synthesis, high cost, low purity, and poor reversibility. Numerous strategies have been proposed to overcome these limitations, including increase in the purity and reduction of the synthesis cost of these materials by optimizing the boron/hydrogen source, reducing agent, and reaction methods used. This review summarizes recent progress in the preparation and regeneration of single-cation (e.g., NaBH4, LiBH4 and Mg(BH4)2) and dual-cation borohydrides. Ouyang developed a practical, facile, and low-cost method for regenerating MBH4 (M=Na, Li) by ball milling of MBO2 center dot xH2O and cheap Mg/MgH2. In this method, the direct hydrolysis of MBH4 produces MBO2 center dot xH2O, and the hydrogen needed to regenerate MBH4 comes from the crystallization water of MBO2 center dot xH2O. This method has the potential to overcome the prevailing challenges of decreasing the synthesis cost and increasing the reversibility of metal borohydrides.

Hydrogen energy has attracted considerable attention as a promising alternative to petroleum. Herein, a novel (Al-x%Li)-y%NaBH4 composite with a core-shell structure has been designed and synthesized by a one-step ball-milling method for generating hydrogen by hydrolysis. NaBH4 formed a surface coating that completely wrapped the Al-x%Li alloy particles to prevent agglomeration and oxidation. Meanwhile, the synergism between the Al-Li alloy and NaBH4 promoted the hydrogen generation rate (HGR) of the composite. The total hydrogen release content of (Al-10%Li)-10%NaBH4 reached 1468.8 mLmiddotg-1, with the highest HGR reaching 4393.7 mLmiddotg-1middotmin-1 at 303 K. The (Al-x%Li)-y%NaBH4 composites also exhibited outstanding hydrolysis capacity during reaction with a near-stoichiometric amount of added CoCl2 solution. The hydrogen emission exceeded 90% when only twice the amount of stoichiometric CoCl2 solution was injected. The hydrogen mass density of the total system increased to more than 2.3 wt% from approximately 0.6 wt% with the addition of 10 stoichiometric solution, indicating the practical application of the portable fuel cell in conserving the total volume of the facility.(c) 2022 Elsevier B.V. All rights reserved.

The effect of Ag nanowires (NWs) on the optical properties of optoelectronic polymer poly[2-methoxy-5-(2ethylhexyloxy)-1,4-phenylenevinylene] (MEH-PPV) have been systemically investigated. The decoration of Ag NWs with an average diameter of 160 nm leads to improved absorption and photoluminescence (PL) ability due to the coexistence of localized surface plasmons and propagating surface plasmons. Results of steady-state spectra exhibit 180% enhancement of absorption and 190% enhancement at ~630 nm of PL. Temperature and excitation intensity dependent PL measurements demonstrate that Ag NWs can effectively suppress non radiative recombination and enhance radiative recombination. Time-resolved PL measurement reveals the interaction between plasmons and interchain species plays a dominant role in the enhanced PL. These results will provide an effective way for further improving the optical properties of optoelectronic devices based on conjugated polymers.

Superabsorbents, used in the removal of oils and organic solvents, play a extremely important role in environmental protection. There is an urgent demand for environment-friendly and high-performance absorbent materials with high selectivity for oils and organic solvents, and is also challenging. Herein, a facile and fluorine-free method to fabricate Polyacrylonitrile @ Polydimethylsiloxane (PAN@PDMS) coaxial nanofibrous aerogels (NFAs) was developed. The steps for synthesis included: coaxial electrospinning - freeze drying - in situ polymerization. The obtained PAN@PDMS NFAs displayed excellent absorption capacities for various oils and organic solvents (55.43-127.37 times of its weight), and efficient water-in-oil emulsions separation with high separation flux (1718 +/- 45 L.m(-2).h(-1)) and excellent separation efficiency (above 99.47 wt%). Particularly, the NFAs showed outstanding mechanical resilience (above 83% recovery after repeating 200 cycles at 80% strain) and could be reused by simply squeezing the oil/organic solvent out of it. More importantly, the PAN@PDMS NFAs showed good resistance against various chemicals such as acids and alkalis. Therefore, this study offers a facile methodology for the fabrication of NFAs that are expected to be promising candidate materials for practical oily wastewater treatment in environmental protection.

Organo-montmorillonite (OMnt) has wide applications in paints, clay-polymer nanocomposites, biomaterials, etc. In most cases, the dispersibility and swellability of OMnt dictate the performance of OMnt in the target products. Previous studies have revealed that the properties can be improved when multiple organic species are co-introduced into the interlayer space of montmorillonite (Mnt). In the present study, single surfactant erucylamide (EA), dual-surfactants cetyltrimethyl ammonium bromide (CTAB) and octadecyltrimethyl ammonium chloride (OTAC), and ternary-surfactants EA, CTAB, and OTAC were co-introduced into Mnt by solution intercalation. The resulting OMnts were characterized by powder X-ray diffraction (XRD), Fourier-transform infrared (FTIR) spectroscopy, thermogravimetry-differential thermogravimetry (TG-DTG), water contact-angle tests, scanning electronic microscopy (SEM), laser particle-size analysis, and swelling indices. Mnt co-modified by ternary CTAB, OTAC, and EA led to a large d001 value (4.20 nm), surface hydrophobicity with a contact angle of 95.6°, swellability (50 mL/g) with small average particle sizes (2.1−2.8 μm) in xylene, and >99% of the OMnt particles were kept as <5 μm in deionized water. The formation of EA-modified-Mnt was proposed according to hydrophobic affinity, hydrogen bonding, and van der Waals forces. The nanoplatelets of the CTA+, OTA+, and EA co-modified OMnts in xylene were assembled into a house-of-cards structure by face-to-edge and edge-to-edge associations. The electrostatic attractions, electrostatic and steric repulsions, and hydrophobic interactions were responsible for the good dispersibility of OMnt in xylene. The ternary surfactant co-modified OMnt with high dispersion and swellability will make OMnt better suited for real-world applications.

Abstract The addition of clay minerals in drilling fluids modifies the dispersion's viscosity. In this article, scientific advances related to the use of clays and clay minerals (bentonite, palygorskite, sepiolite and mixtures of clay minerals) in drilling fluids are summarized and discussed based on their specific structure, rheological properties, applications, prevailing challenges and future directions. The rheological properties of drilling fluids are affected by the temperature, type of electrolytes, pH and concentration of clay minerals. Bentonites are smectite-rich clays often used in drilling fluids, and their composition varies from deposit to deposit. Such variations significantly affect the behaviour of bentonite-based drilling fluids. Palygorskite is suitable for use in oil-based drilling fluids, but the gelation and gel structures of palygorskite-added drilling fluids have not received much attention. Sepiolite is often used in water-based drilling fluids as a rheological additive. Dispersions containing mixtures of clays including bentonite, kaolin, palygorskite and sepiolite are used in drilling fluids requiring specific features such as high-density drilling fluids or those used in impermeable slurry walls. In these cases, the surface chemistry–microstructure–property relationships of mixed-clay dispersions need to be understood fully. The prevailing challenges and future directions in drilling fluids research include safety, ‘green’ processes and high-temperature and high-pressure-resistant clay minerals.

Chrysotile asbestos has excellent physical and chemical properties, but its high biotoxicity is very damaging to human health, due to its durability, high aspect ratio, and the exist of iron. By simple chemical treatment of chrysotile asbestos, silicon oxide nanofibers rich in hydroxyl groups on the surface can be prepared. In this study, we synthesized a series of polyurethane/silicon oxide nano-composite coatings with special performance following a blending method that introduced silicon oxide nanofibers into polyurethane. Measurement results revealed that, silicon oxide nanofibers can be used as reinforcing filler to increase the hardness, shear strength, wear resistance, thermal stability and chemical resistance of polyurethane coatings. And the optical performance test results indicate that the transmittance of the polyurethane coating decreased with increasing of silicon oxide nanofibers contents. However, the ultraviolet shielding effect of the polyurethane coating was improved to a certain extent with the addition of silicon oxide nanofibers.

Purpose The paper aims to provide a facile approach to the synthesis of polyurethane–silica nanocomposites by introducing self-made aqueous silica sols with different particle sizes into polyurethane materials. This paper investigates the effects of the silica nanoparticles on the polyester polyol, as well as the physical properties and transmittance of the hybrid polyurethane coatings. Design/methodology/approach Colloidal silica particles of different sizes were obtained using a sol–gel process and were then embedded into polyester polyol by in-situ polymerization. These polyester polyol–silica resins were synthesized using an azeotrope process, using xylene to remove the water generated in the system and present in the dispersion medium for the colloidal silica. The polyester polyol–silica resins were further cured using isocyanate trimers to form polyurethane–silica hybrid films. Findings The paper observed that the viscosity of the polyester polyol–silica nanocomposite resins increased and their appearance changed from transparent to ivory white as the particle size of the added silica was increased. It was found that increasing the hydroxyl content of the silica improved the film transmittance in the visible light region. However, the transmittance decreased sharply once the diameter of the silica particles reached 100 nm. Research limitations/implications Because of the limitation of experimental conditions, some performances have not been tested. Therefore, researchers are encouraged to conduct further tests. Practical implications The paper provides a method of preparing hybrid polyurethane film by using silica; the results indicate that the introduction of nano-silica can improve the wear resistance and glass transition temperature of polyurethane coatings. Originality/value The results obtained in this study will be extremely useful to enhance the understanding of organic–inorganic hybrid materials.

Catalytic glycerol dehydration provides a sustainable route to produce acrolein because glycerol is a bioavailable platform chemical. However, in this process catalysts are rapidly deactivated due to coking. This paper examines and discusses recent insights into coking of catalysts during catalytic glycerol dehydration. The nature and location of coke and the rate of coking depend on feedstock, operating conditions, and the acidity and pore structure of the solid catalysts. Several methods have been suggested for inhibiting the coking and slowing the deactivation of catalyst, including (1) cofeeding of oxygen, (2) tuning of the pore size of the solid acid catalysts, (3) doping noble metals (Ru, Pt, Pd) into the solid acid catalysts, and (4) designing new reactors. The present methods for inhibiting coking are still unsatisfactory. The deactivated catalysts can be regenerated by removing coke. Nevertheless, the rapid deactivation of the regenerated catalyst remains problematic. The literature survey indicates that the exact chemical compositions of the coke on the catalyst during glycerol dehydration remain elusive. The thermodynamics, kinetics, and mechanism of coking need to be probed so as to advance the development of a catalyst with high activity, selectivity, and resistance to coking to put the catalytic glycerol dehydration into practice.

In this study, we synthesized semi-crystalline thermosetting polymer that have two-way-reversible shape memory effect (2W-SME) with a single crystalline phase and an amorphous phase. The polymer could be synthesized readily and its glass transition temperature (Tg) could be tuned over a wide range. The effect of acrylic monomers on the degree of cross-linking, the effects of different conditions, the applied stress, the acrylic monomers used, and the phase ratio of the crystalline and amorphous domains on the 2W-SME were studied. Measurement results confirmed that the polymer showed the 2W-SME and, the strongest 2W-SME achieved under the optimized conditions corresponded to a reversible deformation of 8.5%.

Exfoliating montmorillonite (Mt) to nanolayers is a crucial step during producing clay/polymer nanocomposites (CPN). Only well-exfoliated and well-dispersed Mt. nanolayers in the polymer matrix can significantly improve the properties of the nanocomposites. This review examines the latest scientific advances in the exfoliation methods of Mt., the insights into the exfoliation mechanisms, and the peculiar functionalities of the resultant CPN. The direct exfoliation of Mt. dispersed in water or organic solvents is often intensified by ultrasonication. Grinding of Mt. in the form of solid in a high-energy ball mill can directly exfoliate Mt. to some extent. Exfoliating Mt. for producing CPN is mainly achieved through so-called in situ exfoliation, solution exfoliation and melt exfoliation. The Mt./polymer nanocomposites exhibit typically improved barrier properties, mechanical strength, thermal stability, and fire retardancy. The literature survey suggests that future work should place emphases on developing green and effective exfoliation methods, and deepening understanding of exfoliation mechanisms and the interfacial interactions between the inorganic Mt. nanolayers and organic monomers/polymers. Future research is suggested to assembling exfoliated Mt. nanolayers with functional polymeric molecules or other nano-scale building blocks to produce functional hierarchical nanomaterials with practical applications.

The key problem which needs to be solved during the commercialization process of the organic light emitting diode (OLED) lighting technology is how to improve the efficiency and stability of optoelectronic materials. In order to solute this issue, we explore the regulation of Ag nanoparticles (NPs) on the photoluminescence (PL) characteristics of an efficient organic optoelectronic polymer poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylene-vinylene] (MEH-PPV). Because of the coupling between the localized surface plasmons from the Ag NPs and the PL emission of the MEH-PPV, the Ag NPs could effectively enhance the PL intensity, modulate the spectral line shape and shorten the lifetime of interchain species. The temperature-dependent PL measurement exhibits that with the introduction of Ag NPs, the thermal exchange process between the sample and the surrounding environment becomes more effective, and the activation energy decreases from 448 to 318 meV. The excitation intensity (EI)-dependent PL measurement demonstrates that the thermal accumulation effect and the nonlinearity of El-dependent PL enhancement are both suppressed by the Ag NPs. The results of this study will provide experimental guidance to the design and fabrication of OLED devices with high efficiency and stability. (C) 2018 Elsevier B.V. All rights reserved.

Polyurethanes are a class of special polymers with high tunable properties,and have been widely used in many fields due to the versatility in selection of raw materials.In this article,the trends in the development status and research progress of high performance polyurethanes were introduced,the application and research orientation for functional polyurethanes were summarized,and the application problems of polyurethanes in different fields were discussed.Finally,the development prospect of functional polyurethane materials in different fields was prospected.