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A facile oxidation strategy is proposed to in situ grow a hydrophobic, thin and uniform triplex surface coating on Nd–Fe–B, which ensures outstanding anti-corrosion performance, accompanied with synergistic magnetic and mechanical performance.

By manipulating the Zn2+ coordination environment, electrolytes with diverse Zn2+–En configurations effectively inhibit zinc dendrite growth and side reactions.

Seeking all-nature derived antibacterial agents with effective disinfection function, high human safety as well as environment-friendly characteristics are highly required in the food industry. Herein, we report the lactoferrin-thymol (LF-Thy) complex as an effective killing agent against Gram-negative Escherichia coli (E. coli) and Gram-positive Staphylococcus aureus (S. aureus). The multi-spectroscopy results clearly demonstrate the combination of LF and Thy to form the LF-Thy complex, accompanied with LF conformation variations including the increase in the hydrophobicity of amino acid residues and changes in the types of secondary conformation distribution in LF. Molecular docking results show that LF exhibits three possible binding sites and five predicted stable binding modes for Thy with the help of hydrogen bonding and hydrophobic interactions. Moreover, LF-Thy demonstrated a significantly higher antibacterial ability compared to LF and displays effective disinfection function against E. coli and S. aureus. The minimum inhibitory concentration (MIC) of LF toward E. coli and S. aureus is >40 mg mL-1 and 40 mg mL-1, which decreases to 10 mg mL-1 and 5 mg mL-1 after combination with Thy, respectively. This work demonstrates the promising antibacterial activities of the LF-Thy complex and provides an alternative agent for combating bacterial infection in the food industry, which holds great potential for promoting the development of the all-natural healthcare food complex.

The demand for high-performance spintronic devices has boosted intense research on the manipulation of magnetism in van der Waals (vdW) magnets. Despite great efforts, robust ferromagnetic transitions above room temperature still face significant hurdles. Strain engineering can reversibly regulate magnetic exchange, but the degree of regulation is still impractical for most magnetic applications. Hereby we employ a large-strain transferrer to produce tunable strains of up to 4.7%, which induces authentic room-temperature ferromagnetism in large-area Fe3GeTe2 nanoflakes with 20-fold improvement in magnetization. The record increment of the Curie temperature (TC) of well above 400 K originates from the strain-enhanced magnetic anisotropy and excellent magnetoelastic coupling. The correlation between the emerging ferromagnetism and Raman spectral evolution is also established, which complements well the TC phase diagram in a large-strain region. In addition, an unusual exchange bias effect with a vertical magnetization shift is tracked for the first time upon bending, which reveals the hidden competition between antiferromagnetic and ferromagnetic coupling. The reversible strain manipulation of single-domain ferromagnetic order in a single nanoflake further opens up a route to develop low-power wearable spintronic devices. The findings here provide vast opportunities to exploit the possibility of practical applications of more vdW magnets.

A bottom-up approach was developed to prepare TEMPO radical decorated hollow aromatic frameworks (HPAF-TEMPO) by using TEMPO radical functionalized monomers and SiO2 nanospheres as templates. The accessible inner layer, high density of TEMPO sites, and hybrid micro-/mesopores of the HPAF-TEMPO enable the aerobic oxidation of a broad range of alcohols with high efficiency and excellent selectivity.

With the growth of chemical data, computation power and algorithms, machine learning-assisted high-throughput virtual screening (ML-assisted HTVS) is revolutionizing the research paradigm of new materials. Herein, a combined ML-assisted HTVS and experimental approach was applied to accelerate the search for energetic melt-castable materials with promising properties. The ML-assisted HTVS system is composed of high-throughput molecular generation (in a heuristic enumeration method) and five machine learning-based property prediction models (including density, melting point, decomposition temperature, detonation velocity, and detonation pressure). Using this system, we rapidly targeted 136 promising candidates from a generated molecular space containing 3892 molecules. With extensive efforts on experimental synthesis, eight new energetic melt-castable materials (MC-1 to MC-8) were obtained, and their measured properties were in good agreement with the predicted results. This work verifies the effectiveness of the combined ML-assisted HTVS and experimental approach for the accelerated discovery of energetic melt-castable materials.

Prussian blue analogues hold great promise as cathodes in sodium ion batteries. Among Prussian blue analogues, manganese hexacyanoferrate is desirable because of its high working voltage, as well as its high specific capacity and low cost. However, poor cycling stability and unsatisfactory rate capability of manganese hexacyanoferrate, which are mainly caused by poor intrinsic conductivity, phase transition, side reactions, and transition metal dissolution, extremely limit its practical application. In this work, we demonstrate a high-rate and long-life MnHCF@PEDOT sodium ion battery cathode through a facile in situ polymerization method. Benefitting from the synergistic effect of the inhibited Mn/Fe dissolution, suppressed phase transition, and improved capacitive storage, the composite electrode exhibits a high capacity of 147.9 mA h g−1 at 0.1C, 95.2 mA h g−1 at a high rate of 10C, and 78.2% capacity retention after 1000 cycles. Furthermore, even at a low temperature of −10 °C, MnHCF@PEDOT still delivers a high capacity of 87.0 mA h g−1 and maintains 71.5 mA h g−1 (82.2%) after 500 cycles.

Scalable and low cost fabrication of light weight flexible electromagnetic (EM) wave absorbers is highly desirable for the rapid development of wearable electronic devices. A simple method has been developed involving incorporation of rationally designed FeNi3/Mo2C into cellulose fibers in the formation of thin and flexible absorbing papers with tunable electromagnetic parameters. High-performance absorption has been achieved with the minimum reflection loss (RL) reaching −51.50 dB at 13.7 GHz and an effective absorption bandwidth of 5.1 GHz with a thickness of 2.0 mm due to the synergic effects of dielectric and magnetic loss. For emerging flexible absorbers, accurate electromagnetic measurements by using a conventional coaxial method are challenging without the addition of wax or paraffin as the solidification agent. A stacking and compressing method has been developed to prepare standard-sized core samples for coaxial measurements for which the validity has been confirmed by comparison with the waveguide and arch methods. Consequently, not only a new type of effective EM absorber has been developed and verified by all the available measurement methods, but this simple and scalable method applied to fabricate flexible electronic devices is also extendable for applications in sensing, catalysis and energy storage.

Developing lightweight and thin electromagnetic (EM) wave absorbers with a broad bandwidth remains a major challenge for reducing EM pollution originating from the rapidly increasing amount of electronics. Herein, porous Co9S8 nanotubes synthesized through a facile self-template method are applied as a single-component EM wave absorber. Based on percolation theory, an appropriate balance between excellent impedance matching and strong loss ability can be achieved for the Co9S8/paraffin composite with 30 wt% filler loading, giving rise to a broad effective absorption bandwidth almost covering the entire Ku band, or X band with varied Co9S8 loadings. This study provides a new concept for the design of single-component EM wave absorbing materials with even superior performance to those of many multicomponent absorbers.

Benefiting from the abundance of sodium, rechargeable sodium ion batteries (SIBs) are preferred over lithium ion batteries (LIBs) in large-scale storage of electrical energy. Low-cost Prussian blue (PB) is a promising cathode because of its ease of synthesis and rigid open framework. Nevertheless, the less activated low spin Fe in FeC6 octahedron lowers the average potential and the overall capacity, while the lattice vacancies and side reactions between low spin Fe and the electrolyte shortens PB's cycling life. Herein, PB with a controllable gradient nickel substitution, which features a high-Ni-content outer layer and low-Ni-content inner layer in a single grain, is demonstrated for high performance sodium storage. The high-Ni-content outer layer efficiently prevents side reactions, ensuring excellent cycling stability, while a small amount of nickel ions in the inner layer efficiently activates the low spin Fe for achieving high capacity. Taking the above synergistic advantages, our gradient-PB exhibits a high reversible capacity of 114 mA h g−1 at 100 mA g−1 and 84 mA h g−1 at 1 A g−1 with very stable cycling for up to 1000 cycles. Gradient substitution in PB analogues provides a novel strategy for exploring high performance PB-based cathodes for SIBs.

High capacity anode materials have been wandering around the corner of commercialization for advanced lithium ion batteries. Nanostructuring these electrochemical active materials through reserving large void spaces have been extensively utilized to extend cycling stability in terms of volume change view. However, the ultra-low volumetric capacity associated with the loosely-packed nano-sized materials is a critical damage for the practical applications of high capacity materials. Here in a highly dense nanocomposite anode, we successfully eliminate the cycling failure of high capacity anode by suppressing atom migration during lithiation/delithiation, demonstrating a novel approach of spatially-confined electrochemical reactions through which the atoms/clusters can be rapidly lithiated/delithiated at their original sites. The spatially-confined lithiation/delithiation effectively avoids inter-cluster migration and perfectly keeps full structure integrity during prolonged cycling. Impressively, a volumetric capacity as high as 6034.5 mAh cm-3 (1206.9 mAh g-1, 86.4% of the first discharge capacity) can still be maintained after 200 stable cycles and 4704.0 mAh cm-3 (940.8 mAh g-1) is retained at an ultra-high current density of 20 A g-1. This spatially-confined lithiation/delithiation offers novel insight to enhance cycling performance of high capacity anode materials. The successful demonstration of dense anode may shed light on the practical applications of high capacity materials for the upgrade of lithium ion batteries.

The compound Tm5Ge4 is the last one in the family of R5Ge4 (R = rare earth elements with magnetic moments) compounds (exclusive of Pm and Eu) whose magnetic properties are still unknown. We prepared high quality Tm5Ge4, and report the detailed crystal structure and magnetic properties. Tm5Ge4 crystallizes in the Sm5Ge4-type orthorhombic structure at room temperature, and orders antiferromagnetically at = 13 and TN = 21 K. The paramagnetic Curie temperature of Tm5Ge4 is positive (θp = 16 K), and the effective magnetic moment (peff = 7.4 μB/Tm) is in good agreement with the theoretical value of 7.56 μB/Tm3+. The ac susceptibility of Tm5Ge4 shows obvious frequency dependence behaviors suggesting the existence of a ferromagnetic cluster in the antiferromagnetic substance. According to the magnetic hysteresis loop, the intrinsic coercivity of Tm5Ge4 is 2616 Oe at 2 K. Tm5Ge4 exhibits an oscillating magnetocaloric effect owing to a metamagnetic-like transformation induced by a critical magnetic field below 21 K.

Metal Al was ball milled with CaH2 to improve its hydrolysis properties. The effects of reaction temperature and milling conditions on the hydrogen generation performances of Al are investigated. A higher temperature has been shown to be beneficial for the hydrolysis of Al–CaH2 composites. With increasing the added amount of CaH2 and milling time, the grain size of Al is decreased and the protective oxide film on the surface of the Al powder is damaged. The hydrolysis of CaH2 helps to open up the structure of Al grains and provide OH− to enhance the corrosion of Al. As a result, the hydrogen production of Al powder has been greatly optimized, and the addition of CaH2 proves to be more effective than the addition of some other hydrides. The yield and maximum hydrogen generation rate (mHGR) of an Al-10 mol% CaH2 mixture milled for 15 h are 97.8% and 2074.3 mL min−1 g−1, respectively.

MgH2 possesses a high hydrogen capacity and excellent reversibility. However, the high thermal stability and slow sorption kinetics retard its practical application as an on-board hydrogen storage material. In this work, AlH3 and CeF3 were introduced into Mg-based materials for the purpose of improving both the thermodynamic and the kinetic properties of MgH2. DSC-TG analysis shows that the onset hydrogen desorption temperature of MgH2 can be synergistically reduced by 86 °C through the co-addition of 0.25AlH3 and 0.01CeF3. Isothermal desorption measurements demonstrate that the co-addition of AlH3 and CeF3 significantly enhances the hydrogen desorption kinetics of MgH2 with the absence of the induction period in the initial stage and the acceleration of the hydrogen desorption process. In addition, this co-doped MgH2 shows very good cycling stability at 300 °C with a 1 h capacity of 3.5 wt% and a 3 h capacity of 4.5 wt%. Structural analysis by XRD measurements indicates that during the hydrogen desorption process, MgH2 may react with Al (generated from the in situ decomposition of AlH3) to form Mg solid solution and Mg17Al12, which contribute to the thermodynamic improvement of the Mg-based material. In addition, MgH2 may also react with CeF3 to form MgF2 and CeH2–3, which act both as hydrogen diffusion gateways and as an impediment to the grain growth of MgH2 during hydrogen sorption cycling, thus improving the hydrogen desorption kinetics and the cycling stability of MgH2. Finally, it was found that the presence of AlH3 kinetically helps CeF3 to exert its positive effect on the hydrogen desorption properties of MgH2. This work provides a method for simultaneously tailoring the thermodynamic and kinetic properties of MgH2 by the synergistic addition of metal hydride and rare earth fluoride.

Electrical conductivity of SnO(2)-based oxides is of great importance for their application as transparent conducting oxides (TCO) and gas sensors. In this paper, for the first time, an unusual enhancement in electrical conductivity was observed for SnO(2) films upon zinc doping. Films with Zn/(Zn + Sn) reaching 0.48 were grown by pulsed spray-evaporation chemical vapor deposition. X-Ray diffraction (XRD) shows that pure and zinc-doped SnO(2) films grow in the tetragonal rutile-type structure. Within the low doping concentration range, Zn leads to a significant decrease of the crystallite size and electrical resistivity. Increasing Zn doping concentration above Zn/(Zn + Sn) = 0.12 leads to an XRD-amorphous film with electrical resistivity below 0.015 Ω cm at room temperature. Optical measurements show transparencies above 80% in the visible spectral range for all films, and doping was shown to be efficient for the band gap tuning.

We report a room-temperature, facile and scalable strategy for the synthesis of Mn3O4 nanosheet/graphene nanocomposites. An important characteristic of these Mn3O4 nanosheets is their mesoporous nature and they have mesopores which are ∼4 nm in size. Such nanocomposites exhibit a high performance in lithium-ion batteries by virtue of this advantageous structural feature.

Electrical transport behaviors of SnO2-based oxides are absolutely essential, either for the understanding of physiochemical properties, or their practical applications. In this paper, an abnormal change in electrical transport is reported upon cobalt doping. A far-from-equilibrium technique-pulsed spray evaporation chemical vapor deposition (PSE-CVD), is investigated for the fabrication of Sn1-xCoxO2-delta (x = 0-0.18) thin films. Upon cobalt doping, the Hall mobility improves gradually and a ten-fold enhancement was noticed for Sn0.82Co0.18O2-delta relative to pure SnO2 films. This unexpected effect induces a dramatic drop in the electrical resistivity. Post-annealing treatment and XPS investigation indicate that the occurrence of surface-stabilized tin interstitials may be the primary reason for the unusual enhancement in conductivity. Cobalt doping not only generates the interstitial tin cations, but also stabilizes to a great extent their presence at the surface. This study may help to illumine new insight for the understanding of doping strategies, and offer a potential route for transport-related applications.