Rare Metals最新文献

The introduction of fillers boosts the performance of polymer coatings and extends their service life. However, single component fillers are not sufficient for intelligent coatings, and compatibility between the polymer matrix and the filler remains a major challenge. In this study, functional polydopamine (PDA) modified CeO₂/sodium-based montmorillonite (Na-MMT) or CeO₂/calcium-based montmorillonite (Ca-MMT) fillers were designed and fabricated via facile in-situ method. The coatings incorporated with MMT-based fillers that were prepared demonstrated remarkable anti-corrosion capabilities, exceptional antimicrobial resistance, and rapid self-healing properties. Specifically, the low-frequency impedance (|Z|_0.01 Hz) values of PDA/CeO₂/Na-MMT/EP and PDA/CeO₂/Ca-MMT/EP, after being immersed for 30 days, were sustained at 2.24 × 10⁷ and 1.70 × 10⁷ Ω cm², respectively. Additionally, the bacteriostatic rates of the filler against E. coli and S. aureus can both reach above 99.9%, respectively, due to the photothermal effect and synergistic bacteriostatic mechanism of PDA and CeO₂. The scratches healed rapidly within 40 s under near-infrared (NIR) irradiation. This work provides valuable guidance for the utilization of MMT-based sheet fillers for enhanced corrosion-resistant, antimicrobial, and repairable coatings.

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Rapid hole extraction from photoanodes to cocatalysts is a crucial prerequisite for the realization of highly efficient photoelectrochemical (PEC) water splitting. Herein, Mn-doped nickel–iron layered double hydroxides (Mn:NiFe-LDHs), as a co-catalyst, were grafted on bismuth vanadate (BVO) for significantly improved charge transfer and stability simultaneously, in addition to the accelerated water oxidation kinetics. The detailed experimental and theoretical analysis collectively verify that Mn doping increases charge density around Ni and Fe sites. The electron-rich Ni sites boost the kinetics of oxygen evolution reaction and promote the hole extraction simultaneously. Moreover, the electrons are transferred from electron-rich Fe sites to V sites, which effectively restrains the dissolution of V⁵⁺ ions and enhances the stability of BVO photoanodes. Consequently, the resulting Mn:NiFe-LDH/BVO photoanode achieves a remarkable photocurrent density of 5.5 mA cm⁻² at 1.23 V versus reversible hydrogen electrode (RHE) with excellent stability. The construction of electron-rich oxygen evolution cocatalysts provides a promising strategy to promote the hole extraction and increase the stability for improved PEC performance.

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Poly (ethylene oxide) (PEO) solid electrolytes hold great promise in all-solid-state lithium batteries (ASSLBs) with high-energy and safety capabilities. However, the PEO electrolyte is hardly resistant to degrade electrochemically at high voltages (>4 V) in ASSLBs. Herein, we design and prepare a highly efficient and stable PEO-based solid electrolyte (denoted as PEO-L/DT-PEO) applied to high-voltage ASSLBs, in which the Li_6.4La₃Zr_1.4Ta_0.6O₁₂ (LLZTO)-containing PEO (PEO-L) serves as a bulk of the electrolyte and the PEO with dual-salts (LiDFOB and high-concentration LiTFSI) forms an ultrathin coating layer (DT-PEO) covering on PEO-L. With 3% coating layer, the PEO-L/DT-PEO electrolyte exhibits an enhanced decomposition potential (> 4.9 V vs. Li/Li⁺) originating from the high concentration of LiTFSI as well as renders Al foil current collector high anticorrosion by the introduction of LiDFOB. Upon coupling with high-voltage NCM811 cathode, the DT-PEO efficiently suppresses the interfacial degradation kinetics between electrolyte and cathode, and slows down the irreversible phase change of NCM811. The assembled PEO-L/DT-PEO-based Li/NCM811 battery exhibits an excellent cycling stability of remaining 63.0% after 400 cycles at a cutoff voltage of 4.2 V as well as an initial discharge specific capacity of 164.5 mAh g⁻¹ at a rate of 0.4C. This work offers a facile and feasible strategy to overcoming interface decomposition of the PEO electrolyte matching perfectly with high-voltage cathode for high-performance ASSLBs.

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Aqueous zinc-ion batteries (AZIBs) are widely used in energy storage devices due to their low cost and environmental sustainability. Nevertheless, the growth of Zn dendrites and the occurrence of side reactions remain significant barriers to the practical application of AZIBs. Here, a hydrophobic and zinc-compatible solid–electrolyte interface layer of poly(dimethylsiloxane) (PDMS) is in situ grafted on the Zn anode surface via spontaneous hydrolytic condensation reactions. The high viscoelasticity of PDMS and the chemically formed Si–O–Zn bonds synergistically ensure the adaptability and stability of PDMS on Zn anodes. Moreover, the strong hydrophobicity of PDMS shields the direct contact between the Zn anode and the aqueous electrolyte and further optimizes the reversible plating/stripping of Zn. The symmetrical cell assembled with PDMS@Zn anode displays a long lifespan of over 3000 h at 1 mA cm⁻² for 1 mAh cm⁻². The PDMS@Zn||NH₄V₄O₁₀ full cell maintains the specific capacity of 284.8 mAh g⁻¹ after 1200 cycles at 1 A g⁻¹. Overall, our work sheds new light on the Zn electrodeposition process under the mediation of anode interface, offers sustainability considerations in designing stable Zn metal anodes, as well as provides a facile and viable path for stabilizing Zn anodes to achieve dendrite-free and long lifespan.

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The hydrophobic and zincophilic PDMS interface layer, in situ chemical grafted onto the Zn anode, significantly enhances interfacial stability and suppresses dendrite growth through its viscoelastic properties and the formation of Si–O–Zn bonds, accommodating anode volume changes during cycling. The PDMS layer’s hydrophobicity and ionic conductivity further prevent direct Zn-electrolyte contact, inhibit hydrogen evolution, and improve Zn²⁺ diffusion, thereby enhancing reversibility.

The advanced oxidation process presents a perfect solution for eliminating organic pollutants in water resources, and the local microenvironment and surface state of metal reactive sites are crucial for the selective activation of peroxomonosulfate (PMS), which possibly determines the degradation pathways of organic contaminants. In this study, by virtue of the precursor alternation, we constructed the state-switched dual metal species with the porous carbon fibers through the electrospinning strategy. Impressively, the optimal catalyst, featuring the electron-deficient cobalt surface oxidative state and most abundant oxygen vacancies (Ov) with MnO₂ within porous carbon fibers, provides abundant mesoporosity, facilitating the diffusion and accommodation of big carbamazepine molecules during the reaction process. Benefiting from the tandem configuration of carbon fiber-encapsulated nanocrystalline species, a p–n heterojunction configuration evidenced by Mott–Schottky analysis induced local built-in electric field (BIEF) between electron-deficient cobalt and Ov-rich MnO₂ within carbon matrix-mediated interfacial interactions, which optimizes the adsorption and activation of PMS and intermediates, increases the concentration of reactive radicals around the active site, and significantly enhances the degradation performance. As a result, the optimal catalyst could achieve 100% degradation of 20 ppm carbamazepine (CBZ) within only 4 min with a rate constant of 1.099 min⁻¹, showcasing a low activation energy (50 kJ mol⁻¹), obviously outperforming the other counterparts. We further demonstrated the generation pathways of active species by activation of PMS mainly including sulfate radical (·SO₄⁻), hydroxyl radical (·OH), superoxide radicals (·O₂⁻), and singlet oxygen (¹O₂), unveiling their contribution to CBZ degradation. The degradation route of CBZ and toxicity analysis of various intermediates were further evaluated. By anchoring the optimal catalyst onto polyester fiber sponge, the photothermal conversion synergistic monolith floatable catalyst and its easy recovery can be achieved, showing good reproducibility and generalizability in the practical application.

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Fabricating a durable electrocatalyst with performance comparable to noble metals for the alkaline hydrogen evolution reaction (HER) remains a significant challenge. In this work, we introduce a highly efficient and robust electrocatalyst by incorporating rhenium (Re) atoms into CoS nanoflakes (Re-CoS) for alkaline HER. The incorporation of Re atoms into the CoS lattice enhances the hybridization of Co 3d and S 2p orbitals, resulting in an optimized electronic structure that accelerates water dissociation on Co sites and optimizes hydrogen adsorption–desorption on S sites, thereby boosting the HER rate. The optimal Re-CoS catalyst demonstrates a low overpotential of 72 mV at 10 mA cm⁻² in 1 M KOH, along with excellent long-term stability, maintaining its catalytic activity over 200 h without significant degradation. These results suggest that the incorporation of Re atoms into CoS effectively couples the water dissociation and hydrogen ad-desorption steps of alkaline HER, offering a promising strategy for the development of noble metal-like electrocatalysts.

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Pancreatic cancer is highly vulnerable to ferroptosis. Consequently, treatments that target pancreatic cancer through ferroptosis induction demonstrate immense potential for enhancing therapeutic outcomes in this condition. In the present study, we synthesized hollow mesoporous iron oxide nanoparticles (MHFe) using a hydrothermal method. These nanoparticles retained the superparamagnetic properties of iron oxide and its Fenton reaction-catalyzing ability. Meanwhile, they also showed superior drug-loading capacity compared to traditional ferric oxide nanoparticles due to their hollow and mesoporous structure. Under the guidance of a magnetic field, these nanoparticles could accumulate in tumor cells. Following the incorporation of Ce6, a sonosensitizer, the Ce6@MHFe system could generate singlet oxygen under ultrasound treatment to promote tumor cell apoptosis while simultaneously producing hydroxyl radicals through the enhanced Fenton effect of MHFe. This promoted ferroptosis in pancreatic cancer cells, achieving combined therapeutic effects. In vivo experiments confirmed the good biocompatibility of Ce6@MHFe and demonstrated that the nanoparticles could effectively kill tumor cells under magnetic targeting and ultrasound irradiation, thereby inhibiting tumor growth. The findings suggested that these hollow mesoporous iron oxide nanoparticles (Ce6@MHFe) with a high drug-loading capacity, tumor retention ability, and potential for combination therapy have potential for the treatment of various malignancies, including pancreatic cancer.

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Transition metal phosphides (TMPs), with tunable electronic structures and diverse compositions, are promising candidates for electrocatalytic water splitting. However, their unsatisfactory electrical conductivity and tendency to aggregate during reactions result in structural instability, ultimately hindering further improvement of their electrocatalytic performance. To address these issues, a bamboo-leaf-like FeCoP/MXene heterojunction was synthesized by hydrothermal and thermal treatments, utilizing highly conductive MXene as the substrate. Density functional theory (DFT) calculations and experimental characterization reveal that strong Ti–O–Co/Fe covalent bond are formed between MXene and FeCoP through hybridization of O 2p and Co/Fe 3d orbitals, which enhance the structural stability of the interface and facilitate the effective anchoring of FeCoP on the MXene surface. Consequently, the structural stability and electrical conductivity of the catalyst are improved simultaneously. Additionally, interfacial charge redistribution optimizes the Gibbs free energy of hydrogen adsorption at the Co, Fe, and Ti sites while promoting the adsorption and activation of water molecules. These factors interact synergistically, leading to enhanced bi-functional electrocatalytic performance for both the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). In a FeCoP/MXene (+||−) two-electrode system, the catalyst achieves a current density of 10 mA cm^–2 at a potential of 1.5 V, which is superior to the RuO₂ (+)||Pt/C (−) system. The assembled water splitting device exhibits long-term stability for up to 100 h at a current density of 100 mA cm^–2. Furthermore, an anion exchange membrane water electrolyzer (AEMWE) equipped with FeCoP/MXene as both anode and cathode achieves an industrial-grade current density of 500 mA cm^–2 at 1.83 V. These results highlight the critical role of interfacial engineering in enhancing the electrocatalytic performance of TMPs for water splitting and provide valuable insights for the design of novel bifunctional TMP catalysts.

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Electrochemical oxidation of 5-hydroxymethylfurfural (HMFOR), featuring favorable thermodynamics, presents a promising alternative to the conventional oxygen evolution reaction for energy-saving hydrogen (H₂) production coupled with biomass upgrading. However, the multiple proton-coupled electron transfer steps in HMFOR result in sluggish kinetics, highlighting the development of highly efficient electrocatalysts. Herein, a high-entropy amorphous MoCrCoNiZn-S grown on nickel foam (HEAS@NF) is constructed via a metal organic framework-derived strategy to efficiently convert HMF to 2,5-furandicarboxylic acid (FDCA). The abundant active sites on the HEAS@NF facilitate the structural evolution to oxyhydroxides that possess strong reducibility for HMF dehydrogenation, leading to superior HMFOR performance compared to sulfides with fewer metal elements. In situ electrochemical impedance spectroscopy results confirm significantly favored kinetics to HMFOR over OER on the HEAS@NF, resulting in a remarkable 98% HMF conversion, with FDCA yield and Faradaic efficiency of 98% and 94% even at a concentrated 100 mM HMF. A two-electrode flow electrolyzer equipped with the bifunctional HEAS@NF enables simultaneous cathodic H₂ and anodic FDCA production with an electricity saving of 10.8%. This study presents an effective strategy to inspire the exploration of high-entropy catalysts for biomass-assisted H₂ production.

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