Frontiers of Materials Science最新文献

The absorption of high-viscosity oil by traditional oil absorbing materials has always been a challenge. So there is an urgent need to solve the problem of slow absorption of high-viscosity oil. In this work, an emulsion composed of polydimethylsiloxane (PDMS), carbon black (CB) and waterborne polyurethane (solid content 40%) was sprayed on the melamine foam (MF). After volatilization of organic solvents, the photothermal material CB was fixed on the MF framework, making it photothermal. By raising the temperature of the modified foam to accelerate the internal thermal movement of high-viscosity oil molecules around the foam, intermolecular forces are reduced, thereby accelerating the separation process. The absorption capacity of this modified MF towards organic solvents and oil is up to 79 times its own weight. In addition, the mechanical properties of the modified foam are improved to a certain extent, more conducive to the continuous oil–water separation. This photothermal absorption material provides ideas for the rapid removal of high-viscosity oil, heavy oil, etc.

Diabetic foot ulcer (DFU) often evolves into chronic wounds that resist healing over an extended period, sometimes necessitating amputation in severe cases. Traditional wound management approaches generally fail to control these chronic sores successfully. Thus, it arouses a huge demand in clinic for a novel wound dressing to treat DFU effectively. Hydrogel as an ideal delivery system exhibits excellent loading capacity and sustainable release behavior. It also boasts tunable physical and chemical properties adaptable to diverse biomedical scenarios, making it a suitable material for fabricating functional wound dressings to treat DFU. The hydrogel dressings are classified into hemostatic, antibacterial and anti-inflammatory, and healing-promoting hydrogel dressings by associating the pathogenesis of DFU in this paper. The design and fabrication strategies for the dressings, as well as their therapeutic effects in treating DFU, are extensively reviewed. Additionally, this paper highlights future perspectives of multifunctional hydrogel dressings in DFU treatment. This review aims to provide valuable references for material scientists to design and develop hydrogel wound dressings with enhanced capabilities for DFU treatment, and to further translate them into the clinic in the future.

Aqueous Zn//MnO₂ rechargeable zinc-ion batteries (ZIBs) possess potential applications in electrochemical energy storage due to their safety, low cost, and environmental friendliness. However, manganese dioxide as the cathode material has poor cycle stability and low conductivity. In this work, the SnO₂@K-MnO₂ (SMO) composite was prepared using the hydrothermal method followed by the treatment with SnCl₂ sensitization, and its electrochemical characteristics were examined using SMO as the cathode material for ZIBs. The reversible specific capacity reaches 298.2 mA·h·g⁻¹ at 0.5 A·g⁻¹, and an excellent capacity retention of 86% is realized after 200 cycles, together with a high discharge capacity of 105 mA·h·g⁻¹ at 10 A·g⁻¹ and a long-term cycling life of over 8000 cycles with no apparent capacity fade. This cathode exhibits a long cycle life up to 2000 cycles at 2 A·g⁻¹ with the mass loading of 5 mg·cm⁻², and the battery maintains the capacity of 80%. The reversible co-embedding mechanism of H⁺/Zn²⁺ in such a Zn//SMO battery was confirmed by XRD and SEM during the charge/discharge process. This work can enlighten and promote the development of advanced cathode materials for ZIBs.

This paper describes how to produce a wearable dry electrode at a reasonable cost and how to use it for the monitoring of biopotentials in electrocardiography. Smart textiles in wearable technologies have made a great advancement in the health care management and living standards of humans. Graphene was manufactured using the low-cost single-step process, laser ablation of polyimide, a commercial polymer. Graphene dispersions were made using solvent isopropyl alcohol which has low boiling point, nontoxicity, and environmental friendliness. After successive coating of the graphene dispersion on the cotton fabric to make it conductive, the sheet resistance of the resulting fabric dropped to 3% of its initial value. The laser-induced graphene (LIG) cotton dry electrodes thus manufactured are comparable to Ag/AgCl wet electrodes in terms of the skin-to-electrode impedance, measuring between 78.0 and 7.2 kΩ for the frequency between 40 Hz and 1 kHz. The LIG cotton electrode displayed a signal-to-noise ratio of 20.17 dB. Due to its comfort, simplicity, and good performance over a longer period of time, the textile electrode appears suited for medical applications.

In this work, C@Fe₃O₄ composites were prepared through a typical template method with emulsified asphalt as carbon source, ammonium ferric citrate as transition metal oxide precursor, and NaCl as template. As an anode for lithium-ion batteries, the optimized C@Fe₃O₄-1:2 composite exhibits an excellent reversible capacity of 856.6 mA·h·g⁻¹ after 100 cycles at 0.1 A·g⁻¹ and a high capacity of 531.1 mA·h·g⁻¹ after 300 cycles at 1 A·g⁻¹, much better than those of bulk carbon/Fe₃O₄ prepared without NaCl. Such remarkable cycling performance mainly benefits from its well-designed structure: Fe₃O₄ nanoparticles generated from ammonium ferric citrate during pyrolysis are homogenously encapsulated in graphitized and in-plane porous carbon nanocages derived from petroleum asphalt. The carbon nanocages not only improve the conductivity of Fe₃O₄, but also suppress the volume expansion of Fe₃O₄ effectively during the charge–discharge cycle, thus delivering a robust electrochemical stability. This work realizes the high value-added utilization of low-cost petroleum asphalt, and can be extended to application of other transition-metal oxides-based anodes.

There are still many challenges including low conductivity of cathodes, shuttle effect of polysulfides, and significant volume change of sulfur during cycling to be solved before practical applications of lithium–sulfur (Li–S) batteries. In this work, (FeO)₂FeBO₃ nanoparticles (NPs) anchored on interconnected nitrogen-doped carbon nanosheets (NCNs) were synthesized, serving as sulfur carriers for Li–S batteries to solve such issues. NCNs have the cross-linked network structure, which possess good electrical conductivity, large specific surface area, and abundant micropores and mesopores, enabling the cathode to be well infiltrated and permeated by the electrolyte, ensuring the rapid electron/ion transfer, and alleviating the volume expansion during the electrochemical reaction. In addition, polar (FeO)₂FeBO₃ can enhance the adsorption of polysulfides, effectively alleviating the polysulfide shuttle effect. Under a current density of 1.0 A·g⁻¹, the initial discharging and charging specific capacities of the (FeO)₂FeBO₃@NCNs-2/S electrode were obtained to be 1113.2 and 1098.3 mA·h·g⁻¹, respectively. After 1000 cycles, its capacity maintained at 436.8 mA·h·g⁻¹, displaying a decay rate of 0.08% per cycle. Therefore, combining NCNs with (FeO)₂FeBO₃ NPs is conducive to the performance improvement of Li–S batteries.

In situ carbon-coated Co₃Se₄/CoSe₂ (CO_xSe_y) nanoparticles (NPs) attached on three-dimensional (3D) reduced graphene oxide (rGO) sheets were skillfully developed in this work, which involved the environment-friendly hydrothermal method, freeze drying, and selenide calcination. Within the structure, the glucose-derived carbon layer exhibited significantly homogeneous dispersion under an argon environment. This structure not only has enhanced stability, but also can effectively mitigate the volume swell of Co_xSe_y particles. The resulted Co₃Se₄/CoSe₂@C/rGO (CSe@C/rGO) exhibited a specific surface area (SSA) of 240.9 m²·g⁻¹, offering more electrochemically active sites for the storage of energy related to lithium ions. The rGO matrix held exceptional flexibility and functional structural rigidity, facilitating the swift ion intercalation and ensuring the high conductivity and recyclability of the structure. When applied to anodes designed for lithium-ion batteries (LIBs), this material demonstrated distinguished rate and ultra-high reversible capacity (872.98 mA·h·g⁻¹ at 0.5 A·g⁻¹). Meanwhile, its capacity retention reached 119.5% after 500 cycles at 2 A·g⁻¹, with a coulombic efficiency of 100%. This work potentially paves the way for generating fast and powerful metal selenide anodes and initiating LIBs with good performance.

Electrolyte interface resistance and low ionic conductivity are essential issues for commercializing solid-state lithium metal batteries (SSLMBs). This work details the fabrication of a double-layer solid composite electrolyte (DLSCE) for SSLMBs. The composite comprises poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF–HFP) and poly(methyl methacrylate) (PMMA) combined with 10 wt.% of Li_6.4La₃Zr_1.4Ta_0.6O₁₂ (LLZTO), synthesized through an ultraviolet curing process. The ionic conductivity of the DLSCE (2.6 × 10⁻⁴ S·cm⁻¹) at room temperature is the high lithium-ion transference number (0.57), and the tensile strength is 17.8 MPa. When this DLSCE was assembled, the resulted LFP/DLSCE/Li battery exhibited excellent rate performance, with the discharge specific capacities of 162.4, 146.9, 93.6, and 64.0 mA·h·g⁻¹ at 0.1, 0.2, 0.5, and 1 C, respectively. Furthermore, the DLSCE demonstrates remarkable stability with lithium metal batteries, facilitating the stable operation of a Li/Li symmetric battery for over 200 h at both 0.1 and 0.2 mA·cm⁻². Notably, the formation of lithium dendrites is also effectively inhibited during cycling. This work provides a novel design strategy and preparation method for solid composite electrolytes.

The solar-to-hydrogen conversion using the photoelectrochemical (PEC) method is a practical approach to producing clean energy. However, it relies on the availability of photocatalyst materials. In this work, a novel photocatalyst comprising molybdenum telluride quantum dots (MoTe₂ QDs)-modified titanium dioxide nanorods (TiO₂ NRs) was prepared for the enhancement of the PEC water splitting performance after combination with a Al₂O₃ layer using the atomic layer deposition (ALD) technique. MoTe₂ QDs were initially prepared, and then they were loaded onto TiO₂ NRs using a warm water bath-based heating method. After a layer of Al₂O₃ was deposited onto resulted TiO₂ NRs/MoTe₂ QDs, the composite TiO₂ NRs/MoTe₂ QDs/Al₂O₃ was finally obtained. Under simulated sunlight (100 mW·cm⁻²), such a composite exhibited a maximum photocurrent density of 2.25 mA·cm⁻² at 1.23 V (versus RHE) and an incident photon-to-electron conversion efficiency of 69.88% at 380 nm, which are 4.33 and 6.66 times those of pure TiO₂ NRs, respectively. Therefore, the composite photocatalyst fabricated in this work may have promising application in the field of PEC water splitting, solar cells and other photocatalytic devices.

Black phosphorus (BP), a novel two-dimensional material, exhibits remarkable photoelectric characteristics, ultrahigh photothermal conversion efficiency, substantial specific surface area, high carrier mobility, and tunable band gap properties. These attributes have positioned it as a promising candidate in domains such as energy, medicine, and the environment. Nonetheless, its vulnerability to light, oxygen, and water can lead to rapid degradation and loss of crystallinity, thereby limiting its synthesis, preservation, and application. Moreover, BP has demonstrated cytotoxic tendencies, substantially constraining its viability in the realm of biomedicine. Consequently, the imperative for surface modification arises to bolster its stability and biocompatibility, while concurrently expanding its utility spectrum. Biological macromolecules, integral components of living organisms, proffer innate advantages over chemical agents and polymers for the purpose of the BP modifications. This review comprehensively surveys the advancements in utilizing biological macromolecules for the modifications of BP. In doing so, it aims to pave the way for enhanced stability, biocompatibility, and diversified applications of this material.