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Plastics have become omnipresent in modern life due to their versatility and durability. However, this convenience comes at the cost of substantial waste generation. The inherent chemical stability of plastics complicates its recycling, leading to environmental pollution and ecological threats. This mini-review highlights recent advancements in addressing this challenge by oxidative transformation of polyethylene (PE) into new functional polymers, value-added chemicals, and carbon-based materials. We first discuss the introduction of hydroxyl, carbonyl groups onto PE with a focus on the functionalization degree and selectivity. Subsequently, approaches for PE oxidation into dicarboxylic acids and short-chain oxidized PE are described and compared, with an emphasis on the tandem reactions for converting mixed dicarboxylic acids into other value-added chemicals. We also briefly discuss the oxidative transformation of PE into carbon-based materials and summarize the progress in qualitative and quantitative analysis of oxidation products. Finally, we conclude this mini-review by highlighting the challenges and opportunities in the field. [ABSTRACT FROM AUTHOR]

Enveloped viruses encased within a lipid bilayer membrane are highly contagious and can cause many infectious diseases like influenza and COVID-19, thus calling for effective prevention and inactivation strategies. Here, we develop a diatomic iron nanozyme with lipoxidase-like (LOX-like) activity for the inactivation of enveloped virus. The diatomic iron sites can destruct the viral envelope via lipid peroxidation, thus displaying non-specific virucidal property. In contrast, natural LOX exhibits low antiviral performance, manifesting the advantage of nanozyme over the natural enzyme. Theoretical studies suggest that the Fe-O-Fe motif can match well the energy levels of Fe2 minority β-spin d orbitals and pentadiene moiety π* orbitals, and thus significantly lower the activation barrier of cis,cis-1,4-pentadiene moiety in the vesicle membrane. We showcase that the diatomic iron nanozyme can be incorporated into air purifier to disinfect airborne flu virus. The present strategy promises a future application in comprehensive biosecurity control. Enveloped viruses encased within a lipid bilayer membrane are highly contagious and cause diseases like influenza and COVID-19, so strategies for their prevention and inactivation are needed. Here, the authors develop a diatomic iron nanozyme with lipoxidase-like activity for the inactivation of enveloped viruses, where the diatomic iron sites destroy the viral envelope via lipid peroxidation. [ABSTRACT FROM AUTHOR]

Nature Communications published a correction notice for the article "Aqueous rechargeable zinc/sodium vanadate batteries with enhanced performance from simultaneous insertion of dual carriers." The correction addressed errors in Fig. 5c, where some ex situ FTIR data were mistakenly plotted identically. The correct data for the Zn/NVO batteries at different charge/discharge states have been provided in the new Article file, and the Source Data have been updated accordingly. The correction does not impact the conclusions of the original work. [Extracted from the article]

Synchronously reducing/self-assembling strategy on Zn substrate was designed to fabricate large-area cation-doped hydrated V2O5/multi-walled carbon nanotube (D-HVO/MWCNT) composite films. Interestingly, the Zn2+ ions are simultaneously doped in hydrated V2O5 during the assembly process, which will be beneficial to the high electrochemical performance of hydrated V2O5. By further combining 3D conductive MWCNT network, the freestanding D-HVO/MWCNT composite films display high capacity, excellent rate capability, and remarkable long-term cycling performance (up to 10,000 cycles with a high capacity retention of 98.5%). Moreover, owing to the high conductivity and flexibility of the D-HVO/MWCNT composite films, the soft-packaged aqueous zinc-ion batteries (ZIBs) were constructed based on such composite films. The devices exhibit stable electrochemical performance even under different bending states. Therefore, such a strategy provides a promising route to achieve large-area carbon and metal oxides-based composite films with high performance and good flexibility. [ABSTRACT FROM AUTHOR]

Aqueous rechargeable metal batteries are intrinsically safe due to the utilization of low-cost and non-flammable water-based electrolyte solutions. However, the discharge voltages of these electrochemical energy storage systems are often limited, thus, resulting in unsatisfactory energy density. Therefore, it is of paramount importance to investigate alternative aqueous metal battery systems to improve the discharge voltage. Herein, we report reversible manganese-ion intercalation chemistry in an aqueous electrolyte solution, where inorganic and organic compounds act as positive electrode active materials for Mn2+ storage when coupled with a Mn/carbon composite negative electrode. In one case, the layered Mn0.18V2O5·nH2O inorganic cathode demonstrates fast and reversible Mn2+ insertion/extraction due to the large lattice spacing, thus, enabling adequate power performances and stable cycling behavior. In the other case, the tetrachloro-1,4-benzoquinone organic cathode molecules undergo enolization during charge/discharge processes, thus, contributing to achieving a stable cell discharge plateau at about 1.37 V. Interestingly, the low redox potential of the Mn/Mn2+ redox couple vs. standard hydrogen electrode (i.e., −1.19 V) enables the production of aqueous manganese metal cells with operational voltages higher than their zinc metal counterparts. Multivalent metal batteries are considered a viable alternative to Li-ion batteries. Here, the authors report a novel aqueous battery system when manganese ions are shuttled between an Mn metal/carbon composite anode and inorganic or organic cathodes. [ABSTRACT FROM AUTHOR]

Electrocatalysis, as the nexus for energy storage and environmental remediation, requires developing low-cost and high-performing heterogeneous catalysts. Compared with the single atom catalysts (SACs), dual-atom catalysts (DACs) are attracting ever-increasing interest due to their higher metal loading, more versatile active sites and unique reactivity. However, controlled synthesis of DACs remains a great challenge, and their electrocatalytic applications are still in infancy. This review first discusses the synthesis of DACs by highlighting several synthetic strategies. Subsequently, we exemplify the unique reactivities of DACs in electrocatalytic applications including water splitting, oxygen reduction, carbon dioxide reduction and nitrogen reduction. The structure-activity relations of DACs are specifically discussed in comparison with that of SACs, on the basis of experimental and theoretical studies. Finally, the opportunities and challenges of DACs are summarized in terms of rational design, controlled synthesis, characterization, and applications. [ABSTRACT FROM AUTHOR]

Bacterial culture and drug susceptibility testing are used to identify pathogen infections. Nevertheless, the process requires several days from collection to the identification of bacterial species and drug-resistance patterns. The digital PCR system is a rapidly developing quantitative detection technology widely applied to molecular diagnosis, including copy number variations, single nucleotide variant analysis, cancer biomarker discovery, and pathogen identification. This study aimed to use a droplet digital PCR system to identify bacteria in blood samples and explore its ability to identify pathogen in bacteremia. Then, we designed primers and probes of SWG-9 and COA gene for E. coli and S. aureus to identify in blood samples with the ddPCR system. The system had demonstrated extremely high detection accuracy in blood samples, and the detection rate of E. coli was 13.1–21.4%, and that of S. aureus was 50–88.3%. Finally, blood samples containing both E. coli and S. aureus were tested to evaluate further the accuracy and applicability of this method, indicating the detection rates range from 18.1% to 97%. The ddPCR system is highly promising as a qualitatively and quantitatively screening method for rapidly detecting pathogen. [ABSTRACT FROM AUTHOR]

Surface-enhanced Raman scattering (SERS) has been considered a high sensitivity, specificity, and ultra-fast analytical technique in molecular fingerprint recognition. Herein, a kind of sandwich Au/"star-like" mesoporous SiO2/Ag (Au/MSiO2/Ag) hybrid nanostructure was developed by implementing the electrostatic adsorption and magnetron sputtering technology for SERS application. In the experiment, the decoration density of the MSiO2/Ag nanostructure was conveniently adjusted through tuning the washing times of the silicon wafer in ethanol. The prepared substrate with the optimal geometry structure exhibited an enhancement factor (EF) of 9.2 × 105, a limit of detection (LOD) of 5 × 10−5 M, and a low relative standard deviation value of 5.02%. In the end, the obtained hybrid SERS substrate was used to detect nitrofurazone and an excellent LOD of 1 ppm was achieved. Overall, our novel sandwich Au/MSiO2/Ag hybrid SERS substrate provides a rapid and accurate way of monitoring ultra-low trace antibiotics, which can significantly promote food safety. [ABSTRACT FROM AUTHOR]

Multimetallic nanowires with long-range atomic ordering hold the promise of unique physicochemical properties in many applications. Here we demonstrate the synthesis and study the stability of Cu3Au intermetallic nanowires. The synthesis is achieved by using Cu@Au core-shell nanowires as precursors. With appropriate Cu/Au stoichiometry, the Cu@Au core-shell nanowires are transformed into fully ordered Cu3Au nanowires under thermal annealing. Thermally-driven atom diffusion accounts for this transformation as revealed by X-ray diffraction and electron microscopy studies. The twin boundaries abundant in the Cu@Au core-shell nanowires facilitate the ordering process. The resulting Cu3Au intermetallic nanowires have uniform and accurate atomic positioning in the crystal lattice, which enhances the nobility of Cu. No obvious copper oxides are observed in fully ordered Cu3Au nanowires after annealing in air at 200 °C, a temperature that is much higher than those observed in Cu@Au core-shell and pure Cu nanowires. This work opens up an opportunity for further research into the development and applications of intermetallic nanowires. [ABSTRACT FROM AUTHOR]

Surface-enhanced Raman scattering (SERS) technique is a powerful spectrum analysis technique for the ultra-low molecular trace detection. Conventionally, noble metals like silver (Ag) and gold (Au) are used to prepare the SERS substrates; however, limitations of complicated experimental designs and sophisticated process steps impede their wide applications in practice. Recently, metal oxides arise as a promising material for SERS application, but relatively weak Raman signal enhancement and poor material stability still pose as a challenge. Here, a UV-light-assisted fabrication of MoO3−x/silver nanoparticles (MoO3−x/Ag NPs) film is proposed. In the experiment, the sub-transition-metal-oxide of MoO3−x was used as the Raman chemical enhancement substrate as well as the reducing agent. Through the spin-coating of MoO3−x layer on the silicon substrate and UV-light-assisted reduction of silver nitride (AgNO3) on the MoO3−x layer, a novel MoO3−x/Ag NPs one-layer film was fabricated. Using the Rhodamine B (RhB) as the Raman reporter, SERS measurement shows that enhancement factor (EF) of 1.195 × 106 could be achieved. Moreover, a Raman signal amplifying strategy is further demonstrated by constructing MoO3−x/Ag NPs multi-layer films. And result evidences that maximum gain of 2.07 for the RhB Raman peak at 1280 cm−1 can be obtained on the MoO3−x/Ag NPs three-layer film when referred to that on the MoO3−x/Ag NPs one-layer film. Meanwhile, the EF of the MoO3−x/Ag NPs three-layer film is also improved to 2.985 × 106, giving the minimum detectable concentration of 10−9 M. [ABSTRACT FROM AUTHOR]

Self-charging power systems integrating energy harvesting technologies and batteries are attracting extensive attention in energy technologies. However, the conventional integrated systems are highly dependent on the availability of the energy sources and generally possess complicated configuration. Herein, we develop chemically self-charging aqueous zinc-ion batteries with a simplified two-electrode configuration based on CaV6O16·3H2O electrode. Such system possesses the capability of energy harvesting, conversion and storage simultaneously. It can be chemically self-recharged by the spontaneous redox reaction between the discharged cathode and oxygen from the ambient environment. Chemically self-recharged zinc-ion batteries display an initial open-circuit voltage of about 1.05 V and a considerable discharge capacity of about 239 mAh g−1, indicating the excellent self-rechargeability. Impressively, such chemically self-charging zinc-ion batteries can also work well at chemical or/and galvanostatic charging hybrid modes. This work not only provides a route to design chemically self-charging energy storage, but also broadens the horizons of aqueous zinc-ion batteries. Self-charging power systems integrating energy generation and storage are receiving consideration attention. Here the authors report an aqueous Zn-ion battery that can be self-recharged by the spontaneous redox reaction between cathode and oxygen from ambient environment without external power supply. [ABSTRACT FROM AUTHOR]

With the booming development of portable and wearable electronic devices, flexible energy storage devices have attracted great attention. Among various energy storage devices, aqueous zinc ion batteries (ZIBs) are one of the promising candidates due to their low cost, good safety, high energy and power densities. However, the conventional cathodes of aqueous ZIBs were often prepared by mixing active materials with binders and conductive additives and then coating them onto current collectors. The resultant cathodes often suffer from unsatisfied flexibility. Herein, we fabricated freestanding reduced graphene oxide/ NaV3O8•1.5H2O (RGO/NVO) composite films with interlinked multilayered architecture by a vacuum filtrating process. Such composite films exhibit excellent mechanical property and high electronic conductivity. Owing to unique architecture, they display a high capacity of 410 mA h g−1 and excellent cycling performance up to 2000 cycles with a high capacity retention of 94%. Moreover, RGO/NVO composite films can directly serve as the cathodes of flexible aqueous ZIBs. As a proof of concept, flexible ZIBs were assembled based on the composite films. Impressively, they exhibit stable performance at different bending states, demonstrating great potential application in flexible energy storage devices. [ABSTRACT FROM AUTHOR]

Rapid development of flexible electronic devices is promoting the design of flexible energy-storage devices. Lithium-sulfur (Li-S) batteries are considered as promising candidates for high energy density energy-storage devices. Therefore, flexible Li-S batteries are desired. In this study, we fabricated composite films of freestanding reduced graphene oxide nanotubes wrapped sulfur nanoparticles (RGONTs@S) by pressing RGONTs@S composite foams, which were synthesized by combining cold quenching with freeze-drying and a subsequent reduction process. These RGONTs@S composite films can serve as self-supporting cathodes for Li-S batteries without additional binders and conductive agents. Their interconnected tubular structure allows easy electron transport throughout the network and helps to confine the polysulfides produced during the charge/discharge process. As a result, the RGONTs@S composite films exhibited a high initial specific capacity, remarkable cycling stability, and excellent rate capability. More importantly, the RGONTs@S composite films can serve as electrodes in flexible Li-S batteries. As a proof of concept, soft-packaged Li-S batteries were assembled using these electrodes and they displayed stable electrochemical performance at different bending states. [ABSTRACT FROM AUTHOR]

The development of facile strategies to tune the oxygen vacancy (OV) content in transition metal oxides (TMOs) is paramount to obtain low-cost and stable electrocatalysts, but still highly challenging. Taking NiCoO as a model system, we have experimentally established a facile calcination and electrochemical activation (EA) methodology to dramatically increase the concentration of OVs and provide theoretical insight into how the concentration of OVs affects the performance of spinel TMOs towards the electrochemical hydrogen evolution reaction (HER). A self-supported cathode of OV-rich NiCoO nanowire arrays was found to exhibit higher HER activity and better stability in alkaline media than its counterparts with fewer OVs. The electrocatalytic HER activity was in good agreement with the increasing concentration of OVs in the studied samples. A large current density of 360 mA·cm was reached with an overpotential of only 317 mV. Additionally, such a facile strategy was able to efficiently generate OVs in other TMOs (e.g., CoFeO and NiFeO) for enhanced HER performance. In addition, our theoretical results suggest that the increasing OV concentration reduces the adsorption energy of water molecules and their dissociation energy barrier on the surface of the catalyst, thus leading to performance improvement of spinel TMOs toward the electrochemical HER. This work may open a new avenue to increase the concentration of OVs in TMOs in a controlled manner for promising applications in a variety of fields. [ABSTRACT FROM AUTHOR]

As promising candidates for energy-storage devices, supercapacitors (SCs) have attracted considerable attention because of their unique features, such as their high power density, outstanding rate capability, excellent cycling performance, and safety. The recent boom in portable electronic devices requires high-performance SCs that are flexible, simplified, thin, and integrated. Tremendous efforts have been directed towards the design and integration of planar micro-SCs (MSCs) based on different active electrode materials by various methods. This review highlights the recent developments in the device design of flexible planar MSCs and their integration with other electronic devices. The current challenges and future prospects for the development of flexible MSCs are also discussed. [ABSTRACT FROM AUTHOR]

Herein, we report a bottom-up solvothermal route to synthesize a flexible, highly efficient MoS@SWNT electrocatalyst for hydrogen evolution reactions (HER). Characterization revealed that branch-like MoS nanosheets containing sulfurrich sites were in situ uniformly dispersed on free-standing single-walled carbon nanotube (SWNT) film, which could expose more unsaturated sulfur atoms, allowing excellent electrical contact with active sites. The flexible catalyst exhibited excellent HER performance with a low overpotential (~150 mV at 10 mA/cm) and small Tafel slope (41 mV/dec). To further explain the improved performance, the local electronic structure was investigated by X-ray absorption near-edge structure (XANES) analysis, proving the presence of unsaturated sulfur atoms and strong electronic coupling between MoS and SWNT. This study provides an in-situ synthetic route to create new multifunctional flexible hybridized catalysts and useful insights into the relationships among the catalyst microstructure, electronic structure, and properties. [ABSTRACT FROM AUTHOR]

A highly porous and crystalline metal-organic framework (MOF) ZIF-8 has been synthesized and used for the preparation of a supported rhodium nanoparticle catalyst (Rh@ZIF-8). The material has been characterized by PXRD, TEM, EDX, ICP-AES and nitrogen adsorption. The catalytic properties of Rh@ZIF-8 have been investigated in the hydroformylation of alkenes, with different chain length and structure, to give the corresponding aldehydes, and showed high activity. Furthermore, after the reaction was complete, the catalyst could be easily separated from the products by simple decantation and reused five times without a significant decrease in the activity under the investigated conditions. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

As a type of thin film, two dimensional (2D) reticulate architectures built of freestanding single-walled carbon nanotube (SWCNT) bundles are suitable for scalable integration into devices and nanocomposites for many applications. The superior properties of these films, such as optical transparency, unique electrical properties and mechanical flexibility, result not only from the outstanding properties of individual SWCNTs but also from the collective behavior of the individual tubes, with additional properties arising from the tube-tube interactions. In this review, the synthesis, structure and fundamental properties, such as conductivity, transparency, optical nonlinearity and mechanical performance, of 'freestanding SWCNT bundle network' thin films and nanocomposites, as well as their application as supercapacitors are highlighted. Some long-standing problems and topics warranting further investigation in the near future are addressed. [ABSTRACT FROM AUTHOR]

novel copper-mediated solvothermal method was proposed for synthesizing colloidal spheres of a new composition, palladium iodide (PdI). Typical procedure was designed to involve the introduction of cupric chloride (CuCl) as weak oxidant. CuCl was found to be essential for preventing the easy formation of palladium deposits as well as facilitating the synthesis and assembly. Under the co-effect of CuCl and the surfactant of polyvinylpyrrolidone (PVP), neutral PdI colloidal spheres with narrow size distribution were successfully produced. Such ion-assisted synthetic method is believed to be prospective in producing well-constructed nanostructures. [ABSTRACT FROM AUTHOR]