Developing advanced high‐rate electrode materials has been a crucial aspect for next‐generation lithium ion batteries (LIBs). A conventional nanoarchitecturing strategy is suggested to improve the rate performance of materials but inevitably brings about compromise in volumetric energy density, cost, safety, and so on. Here, micro‐size Nb14W3O44 is synthesized as a durable high‐rate anode material based on a facile and scalable solution combustion method. Aberration‐corrected scanning transmission electron microscopy reveals the existence of open and interconnected tunnels in the highly crystalline Nb14W3O44, which ensures facile Li+ diffusion even within micro‐size particles. In situ high‐energy synchrotron XRD and XANES combined with Raman spectroscopy and computational simulations clearly reveal a single‐phase solid‐solution reaction with reversible cationic redox process occurring in the NWO framework due to the low‐barrier Li+ intercalation. Therefore, the micro‐size Nb14W3O44 exhibits durable and ultrahigh rate capability, i.e., ≈130 mAh g−1 at 10 C, after 4000 cycles. Most importantly, the micro‐size Nb14W3O44 anode proves its highest practical applicability by the fabrication of a full cell incorporating with a high‐safety LiFePO4 cathode. Such a battery shows a long calendar life of over 1000 cycles and an enhanced thermal stability, which is superior than the current commercial anodes such as Li4Ti5O12.

Environment-friendly and low-cost aqueous zinc-ion batteries (ZIBs) have received considerable attention for large-scale energy storage. However, the low coulombic efficiency and potential safety hazards of Zn-metal anodes severely hinder their practical implementations. Herein, for the first time, mixed-valence Cu 2−x Se is proposed as a new intercalation anode to construct Zn-metal-free rocking-chair ZIBs with a long lifespan. It is found that the introduction of lowvalence Cu not only modify active sites for Zn 2+ ion storage, but also optimizes the electronic interaction between the active sites and the intercalated Zn 2+ ion, leading to a favorable intercalation formation energy (−0.68 eV) and reduced diffusion barrier, as demonstrated by first-principles calculation. Ex situ X-ray diffraction, ex situ transmission electron microscopy and galvanostatic intermittent titration technique measurements reveal the reversible insertion/extraction of Zn 2+ in Cu 2−x Se via an intercalation reaction mechanism. Owing to the rigid host structure and facile Zn 2+ diffusion kinetics, the Cu 2−x Se nanorod anode shows an enhanced coulombic efficiency (above 99.5%), outstanding rate capability and excellent cycling stability. The as-fabricated Zn x MnO 2 ||Cu 2−x Se Zn-ion full battery exhibits an impressive electrochemical performance, particularly an ultralong cycle life of over 20 000 cycles at 2 A g −1. This study is expected to provide new opportunities for developing high-performance rechargeable aqueous ZIBs.

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Anti‐biofilm formation on the surface is a severe issue in medical implants, hull surface, and food industry. Antimicrobial peptide, magainin II, was covalently bound to stainless steel surfaces through multi‐step modification. The untreated and modified samples were analyzed by SEM‐EDS, XPS, and contact angle, respectively, which indicated the peptide was immobilized on the surfaces. The antimicrobial tests of modified samples were conducted using Staphylococcus aureus and Escherichia coli, and the results revealed that peptide modified surface decreased the biofilm and bacteria quantity of stainless steel surface.

Manganese oxide is a promising cathode material for rechargeable aqueous zinc-ion batteries (ZIBs). However, the low electronic conductivity and unstable structure evolution of manganese materials often result in poor rate performance and rapid capacity decay. Herein, we design N-doped Na2Mn3O7 (N-NMO) by combining sodium preintercalation and nitridation treatment strategies to stabilize the crystalline structure and reaction interface. Sodium preintercalation not only enlarges the interlayer distance for fast Zn2+ ion diffusion but also serves as a robust pillar to stabilize the crystalline structure during cycling. Meanwhile, the nitridation layer on the surface of Na2Mn3O7 particles is favorable for enhancing the electronic conductivity and inhibiting the cathode dissolution issue during repeated cycling. Consequently, the as-prepared N-NMO exhibits high reversible capacity (300 mAh g–1 at 0.2 A g–1), good rate capability (100 mAh g–1 at 10 A g–1), and outstanding long-term cycling stability (high capacity retention of 78.9% after 550 cycles at 2 A g–1). Considering the facile and simple synthesizing methods, the synergistic engineering of the interlayer structure and interface is expected to provide new opportunities for the development of high-performance Mn-based cathode materials for aqueous ZIBs.

Attachment of marine fouling organisms causes biofouling. The adhesion of destructive organisms can be reduced through surface modification with antibiofilm chemicals. In this study, a direct surface modification between peptide solution with different concentrations and stainless steel was performed, and the reaction mechanism was explained by simulation of the modification process. Results of surface water contact angle and surface hardness indicated the optimal modification concentration of peptide solution was 10 μg/mL. Under the optimal concentration, peptide-modified stainless steel was prepared through the reaction between peptide and 304 stainless steel. Results of scanning electron microscopy equipped with energy dispersive spectrometry, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy demonstrated that the peptide was successfully bound on stainless steel surface. Antimicrobial activity of samples surface was tested against Staphylococcus aureus. The results illustrated that the peptide treated sample surface possesses significant antimicrobial property. The findings presented valuable information on marine antifouling researches. KEYWORDSantibiofilm, bio-modified metallic material, optimal concentration, peptide, simulationIn aquatic environment, conditioning layer induced by microorganisms is easy to form rapidly on the solid surface. 1 Bacteria then adhere on the conditioning layer and secrete biofilms. The biofilms contain extracellular protein and sticky polysaccharide, which make biofilms easy to attach on almost all surfaces exposed to the non-sterile environment and difficult to remove according to the previous research studies. 2 A large number of fouling organisms will be attracted on the biofilms, resulting in biofouling on the surface of the metal. [3][4][5] Biofouling causes great loss in many fields, including medical implants, food industry, and ship transportation. 6,7 Many methods have been utilized to reduce marine biofouling.For example, coatings with heavy metal ions have been used to reduce the adhesion of biofouling organisms. However, the spreading of the ions into the sea water will cause marine environment pollution. Green techniques should be applied into the research on the antifouling in ship transportation. Previous results showed that the changes of surface energy were related with antifouling of metal surface. Biofouling organisms will be difficult to adhere or easy to detach on the materials surface to achieve antifouling if the surface energy is low or ultralow. [8][9][10][11][12][13] A new bioorganic material with lower surface energy which yielded by an unknown reaction of peptides and metals has been reported. 14,15 It revealed that a chemical reaction of the peptide coatings with metals occurred and changed the electronic state of the metal surface. [16][17][18] Wong et al obtained a material by the reaction between polypeptide and stainless steel; moreover, the extent of the reaction could be improved via dopamine addition. 19,20 Davis e...

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