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Two‐dimensional nanomaterials, as one of the most widely used substrates for energy storage devices, have achieved great success in terms of the overall capacity. Despite the extensive research effort dedicated to this field, there are still major challenges concerning capacitance modulation and stability of the 2D materials that need to be overcome. Doping of the crystal structures, pillaring methods and 3D structuring of electrodes have been proposed to improve the material properties. However, these strategies are usually accompanied by a significant increase in the cost of the entire material preparation process and also a lack of the versatility for modification of the various types of the chemical structures. Hence in this work, versatile, cheap, and environmentally friendly method for the enhancement of the electrochemical parameter of various MXene‐based supercapacitors (Ti3C2, Nb2C, and V2C), coated with functional and charged organic molecules (zwitterions—ZW) is introduced. The MXene‐organic hybrid strategy significantly increases the ionic absorption (capacitance boost) and also forms a passivation layer on the oxidation‐prone surface of the MXene through the covalent bonds. Therefore, this work demonstrates a new, cost‐effective, and versatile approach (MXene‐organic hybrid strategy) for the design and fabrication of hybrid MXene‐base electrode materials for energy storage/conversion systems. [ABSTRACT FROM AUTHOR]

The development of new materials for electromagnetic interference (EMI) shielding is an important area of research, as it allows for the creation of more effective and high‐efficient shielding solutions. In this sense, MXenes, a class of 2D transition metal carbides and nitrides have exhibited promising performances as EMI shielding materials. Electric conductivity, low density, and flexibility are some of the properties given by MXene materials, which make them very attractive in the field. Different processing techniques have been employed to produce MXene‐based materials with EMI shielding properties. This review summarizes processes and the role of key parameters like the content of fillers and thickness in the desired EMI shielding performance. It also discusses the determination of power coefficients in defining the EMI shielding mechanism and the concept of green shielding materials, as well as their influence on the real application of a produced material. The review concludes with a summary of current challenges and prospects in the production of MXene materials as EMI shields. [ABSTRACT FROM AUTHOR]

Owing to the surge of energy storage devices, lithium and beyond‐lithium metal ion batteries (MIBs) have gained considerable research attention. The large size and multivalent ions drastically deteriorate the performance of conventional battery electrode materials which demands unique types of structures in order to fulfill the electrode requirements of next‐generation MIBs. Developing atomically thin nanosheets confined in 2D heterostructures is a favorable choice to synergistically handle the deficiencies of individual 2D materials and achieve distinct physical and electrochemical properties, retaining their 2D features. This article sheds light on the significance and characteristics of graphene‐based and beyond‐graphene 2D heterostructures as electrode materials in lithium‐ion, sodium‐ion, potassium‐ion, magnesium‐ion, and aluminum‐ion batteries. In this regard, the pathways for the selection of 2D heterostructures electrode materials and their possible geometric configurations are first recognized. Second, the fundamental science, underlying charge storage mechanisms, and robust interfacial charge transfer processes in 2D heterostructures are discussed comprehensively in the context of recent computational studies. Third, the recent state‐of‐the‐art experimental approaches for the fabrication of novel 2D heterostructures and their performance as anode and cathode materials for MIBs are discussed systematically. Finally, the current challenges facing 2D heterostructures and potential future research directions in the context of advanced MIBs are highlighted. [ABSTRACT FROM AUTHOR]

The advents in flexible and smart technology like wearable electronics have accelerated the demand for high‐performance energy‐storage devices. These devices could significantly reduce the size of the next‐generation wearable smart electronics. A selection of suitable printing technology and its product typically offer a reasonable manufacturing pathway like high deposition rate, low materials waste, scalable fabrication, and high‐performance production. Therefore, the production of novel functional inks with desirable rheological properties that authorize high‐resolution printing, are some major challenges of this technology. This work has an emphasis on the recent advancements in supporting and utilizing liquid metals chemistry to synthesis high‐quality and scalable 2D nanomaterials by liquid‐phase free exfoliation and facile sonication‐assisted methods. These are novel concepts in synthesizing 2D nanomaterials particularly for those which either have not intrinsic layered crystal structures or those with strong interaction between their crystal layers which are difficult to synthesized using conventional approaches. It also provides some potentials to make sustainable ink formulation of such 2D nanostructures for the fabrication of high‐quality screen‐printed patterns for sustainable energy applications. Subsequently, it deals with the possibilities and challenges of printing such 2D nanomaterials (namely, 2D metal oxides) for micro‐supercapacitor and micro‐battery applications on an industrially viable scale. [ABSTRACT FROM AUTHOR]

Cellulose nanocrystals (CNC) are a class of nanoscale biopolymers produced from cellulose sources. CNC materials have gained growing interests which can be attributed to their excellent properties such as excellent biocompatibility, good mechanical properties and high aspect ratio whilst also being an inexpensive material that can be produced from green and renewable sources. Due to the abundant hydroxyl functional groups, the surface of CNC materials are ready to be tuned and functionalized via chemical reactions allowing for many different applications, such as being a reinforcing agent to be incorporated into a hydrophobic polymer matrix. In this review paper, we firstly introduce the general methods for producing CNC from different sources. Different strategies used for surface modification ofCNCare then discussed. Finally, the recent progress on the applications of CNC and CNC composite materials are described in detail. [ABSTRACT FROM AUTHOR]

The main emphasis of the present Highlight paper is to summarise reported works aiming to understand the effect of sulfur and nitrogen doping on graphene nanoplatelets for high capacity electrodes in solid-state rechargeable energy storage devices. Lithium-ion batteries are considered to be one of the most promising energy storage devices which have the potential of integrating the high energy granted by lithium-ion batteries and long cycling life of supercapacitors in the same system. However, the present Li-ion batteries provide only high power density due to the low electrical conductivity of the anode materials. Moreover, there is a need to increase the capacity and kinetic imbalances between the anode and cathode by designing high-power and stable structures for the anode and cathode materials. Graphene nanoplatelets (GnPs) have been intensively explored as anode materials in lithium ion batteries due to their unique structure and outstanding electrochemical properties. The synthesis procedure, structure and electrochemical performance of such materials are discussed extensively in this manuscript. [ABSTRACT FROM AUTHOR]

Surface modification via advanced technologies to manufacture durable coatings for increasing mechanical, chemical, and biological efficacy is an active research area for biomedical industries. The surface and coating/substrate interface play important roles regarding the biological performance. Precise knowledge concerning the interfacial layer in heterostructures is not well understood because of a lack of in situ characterization. Here, we investigate interfacial bonding structures by an electronic model in (i) tantalum-coated titanium alloy (Ta/Tialloy) and (ii) tantalum-silver-coated titanium alloy (TaAg/Tialloy) bilayer interfaces. The tantalum and tantalum-silver thin films were grown onto Tialloy substrates in a high-vacuum system by magnetron sputtering. We use X-ray photoelectron spectroscopy to probe the electronic structure of the so-formed Ta/Tialloy and TaAg/Tialloy bilayer interfaces. The results demonstrate that the thin-film/substrate interfaces exhibit different bonding characteristics. The TaAg/Tialloy exhibits two semiconductor phases in the interfacial layer with a band gap that is larger than that for the Ta/Tialloy. The large band gap semiconductors that evolve at the interface of the TaAg/Tialloy, as well as the elements with high electronegativity in the overlayer, increase the satellite peak intensity in the interface layer and generate interface polarization. There is an associated increase in the interfacial bonding strength by ionic bonding formation that is determined by measuring the hardness of this material system. [ABSTRACT FROM AUTHOR]

There is global interest in improving the mechanical properties of light metals such as aluminum (Al)-based alloys by tailoring their microstructures at the nanometer scale. On the other hand, gold (Au) has been widely applied as a wire bonding material due to its prominent ductility and conductivity. In this study, the microstructure, hardness and elastic modulus of DC magnetron-sputtered aluminum/gold (Al/Au) composite thin films of different thicknesses were investigated. It is shown that in addition to the formation of AlAu phase, additional Al and Au nanosegregated phases also formed. The Al/Au thin films of 600 and 800 nm thickness exhibit the maximum hardness (~5.40 GPa) and elastic modulus (~97.00 GPa). However, film thicknesses of 1000 and 1200 nm demonstrate a reduction in hardness and elastic modulus due to different growth mechanisms and the formation of voids that can be attributed to the Kirkendall phenomenon. [ABSTRACT FROM AUTHOR]

Nanometer-sized grain structures that exhibit a large number of grain boundaries on the surface of a bulk material demonstrate excellent properties relative to their coarse-grained (CG) equivalents. Surface modification using surface mechanical attrition treatment (SMAT) is an option that cab be used to tailor the corrosion, tribological, mechanical, and chemical reaction properties of a surface. SMAT is an effective route to create the nanostructured surface layer. The SMAT process has unique advantages compared with the other coating and deposition techniques for surface nanocrystallization. For example, SMAT does not alter the chemical composition of the nanocrystalline surface layer in the matrix. In addition, SMAT has been demonstrated to activate the material surface layer by surface modification and enhance the atomic diffusivity. This article presents a review of the advantages offered by the SMAT technique for the creation of high performance surface layers. The influence of the created nanocrystalline layer on mechanical, physical, and chemical properties is assessed. Developments and the current status of the surface nanolayer that are formed are evaluated from a physical approach. Finally, prospects for the future development of grain refinement on the surface of a material matrix and potential applications are presented. [ABSTRACT FROM PUBLISHER]

We have previously reported that the silane coating of magnetic nanoparticles (MNPs) of maghemite phase could be used to protect iron oxide cores during plasma heat treatment, and even help to reduce their phase to magnetite with higher magnetization. In this work, an additional layer of an electrically conductive polypyrrole was added on top of the silane-coated MNPs, producing core-shell particles with sizes ranging from 150 to 500 nm. A microwave plasma heat treatment was used to convert the amorphous, already-conductive polypyrrole coatings into a more electrically conductive graphitic structure, while simultaneously reducing the iron oxide phase to magnetite. The treatment produced core-shell particles with better microwave absorption properties over the frequency of 1-18 GHz, with a maximum reflection loss (absorption) of these MNPs at −37 dB at 10.3 GHz for samples containing 70 wt% of plasma-treated core-shell nanoparticles embedded in wax. By comparison, the maximum absorption for the same amount of untreated nanoparticles was only −18 dB at 7.5 GHz. The improved electromagnetic wave absorption properties were due to higher electrical conductivity of the more ordered, graphitic-like polypyrrole shell structures. This relatively simple protocol could thus be used to synthesize highly magnetic and conductive nanocomposites for electromagnetic interference shielding applications, particularly at the high frequency range. [ABSTRACT FROM AUTHOR]

Abstract: Fe3O4/carbon composite nanoparticles were prepared using polystyrene as the carbon source, with a household microwave oven providing the required energy to produce plasma in a partially-evacuated reaction vessel, leading to the high temperatures required for carbonization of the carbon source and formation of nanoparticles. In this process, magnetite nanoparticles actively catalyzed the formation of carbon nanofibers. The resulting composite retained the magnetic properties after this process, which is potentially very useful for producing new additives for electromagnetic shielding nanocomposites. [Copyright &y& Elsevier]

The adjustable structures and remarkable physicochemical properties of 2D monoelemental materials, such as silicene and germanene, have attracted significant attention in recent years. They can be transformed into silicane (SiH) and germanane (GeH) through covalent functionalization via hydrogen atom termination. However, synthesizing these materials with a scalable and low‐cost fabrication process to achieve high‐quality 2D SiH and GeH poses challenges. Herein, groundbreaking 2D SiH and GeH materials with varying compositions, specifically Si0.25Ge0.75H, Si0.50Ge0.50H, and Si0.75Ge0.25H, are prepared through a simple and efficient chemical exfoliation of their Zintl phases. These 2D materials offer significant advantages, including their large surface area, high mechanical flexibility, rapid electron mobility, and defect‐rich loose‐layered structures. Among these compositions, the Si0.50Ge0.50H electrode demonstrates the highest discharge capacity, reaching up to 1059 mAh g−1 after 60 cycles at a current density of 75 mA g−1. A comprehensive ex‐situ electrochemical analysis is conducted to investigate the reaction mechanisms of lithiation/delithiation in Si0.50Ge0.50H. Subsequently, an initial assessment of the c‐Li15(SixGe1‐x)4 phase after lithiation and the a‐Si0.50Ge0.50 phase after delithiation is presented. Hence, this study contributes crucial insights into the (de)lithiation reaction mechanisms within germanane‐silicane alloys. Such understanding is pivotal for mastering promising materials that amalgamate the finest properties of silicon and germanium. [ABSTRACT FROM AUTHOR]

Single-crystal magnetic-responsive core-shell MOF by grafting Fe 3 O 4 nanoparticles onto the UiO-66-NH 2 and their controlled embedding into gas separation mixed matrix membranes was reported. Obtained results confirmed the stimuli-responsive character of the MMOF during their dispersion of MMOF in a well-defined arrays structure in the PMMA matrix. Contrarily, an absence of a magnetic field results in the MMOF aggregation and sedimentation of the particles at the bottom of the membrane. Compared to the non-controlled ones, gas permeability increased by 26.2% for CO 2 and 76.67% for H 2, and selectivity increased 2.95 and 1.49 times for the CO 2 /N 2 and H 2 /CO 2 gas pairs, respectively. Moreover, obtained permeability-selectivity values for the H 2 /CO 2 gas pairs overcome the appropriate modified 2008 Robeson upper bound. [Display omitted] • Synthesis single crystal magnetic MOFs coreshell. • Fabricating Fe 3 O 4 -UiO-66-NH 2 -PMMA mixed matrix membrane. • Using magnetic field for alignment embedding of MMOFs. • Enhancement of H 2 separation and CO 2 capturing. [ABSTRACT FROM AUTHOR]

The integration of solar‐driven interfacial evaporation and electricity co‐generation is considered a promising approach to simultaneously alleviate freshwater scarcity and the energy crisis. However, affected by intermittent solar irradiation/uncontrollable weather, the overall performance of solar‐driven evaporation in the real world is greatly reduced. Herein, inspired by antifreeze proteins in beetles that survive in extreme climates, all‐weather solar‐driven interfacial evaporators with a sandwich structure are designed. The top and bottom layers composed of MnO2‐modified cotton cloth are used for photothermal conversion and water transport, meanwhile, the middle layer made of a phase change microcapsule/hydrogel composite serves for heat storage and release. Under 1 kW m−2 irradiation, the evaporator exhibits a high evaporation rate of 2.67 kg m−2 h−1 and an efficiency of 89.5%. In the dark, the heat released from the phase change layer supports an evaporation rate of 0.43 kg m−2 h−1, 3.6 times that of pure water. Additionally, assembled with a thermoelectric module, the hybrid device achieves a stable output electricity power of 0.42 W m−2 under 1‐sun illumination and a prolonged output for 30 min in the dark. This work provides a novel approach for full‐time solar‐powered steam‐electricity co‐generation and a proof of concept for biomimetic steam generation/heat management integration. [ABSTRACT FROM AUTHOR]

Disposable aluminum cans and plastic bottles are common wastes found in modern societies. This article shows that they can be upcycled into functional materials, such as metal-organic frameworks and hierarchical porous carbon nanomaterials for high-value applications. Through a solvothermal method, used poly(ethylene terephthalate) bottles and aluminum cans are converted into MIL-53(Al). Subsequently, the as-prepared MIL-53(Al) can be further carbonized into a nitrogen-doped (4.52 at%) hierarchical porous carbon framework. With an optical amount of urea present during the carbonization process, the carbon nanomaterial of a high specific surface area of 1324 m2 g−1 with well-defined porosity can be achieved. These features allow the nitrogen-doped hierarchical porous carbon to perform impressively as the working electrode of supercapacitors, delivering a high specific capacitance of 355 F g−1 at 0.5 A g−1 in a three-electrode cell and exhibiting a high energy density of 20.1 Wh kg−1 at a power density of 225 W kg−1, while simultaneously maintaining 88.2% capacitance retention over 10,000 cycles in two-electrode system. This work demonstrates the possibility of upcycling wastes to obtain carbon-based high-performance supercapacitors. [Display omitted] • Upcycle used PET bottles and aluminum cans into the nitrogen-doped hierarchical porous carbons. • Prepared carbon as supercapacitor electrode delivers a high energy density of 20.1 Wh/kg. • Well-defined porous carbon framework is vital to the excellent supercapacitive performance. • This work paves an effective environmental-friendly way to prepare carbon-based supercapacitor. [ABSTRACT FROM AUTHOR]

Due to the ever-increasing plastic waste causing serious environmental problems, it is highly desirable to recycle it into high-value-added products, such as carbon nanomaterials. However, the traditional catalytic carbonization of hydrocarbon polymers is severely prohibited by the complexity of real-world plastic waste due to the existence of halogen-containing polymers. In this study, through a universal combined template based on magnesium oxide and iron(III) acetylacetonate (Fe(acac)3), a three-dimensional hollow carbon sphere/porous carbon flake hybrid nanostructure is prepared from carbonization of plastic waste with high yields (>70 wt%). This approach is not only suitable for hydrocarbon polymers, but also for halogen-containing polymers. Interestingly, the obtained advanced carbon framework exhibits excellent performance in lithium-ion batteries (802 mA h g−1 after 500 cycles at 0.5 A g−1). The present research paves a new avenue to upcycle plastic waste into a high value-added product. [ABSTRACT FROM AUTHOR]

• Flexible, ultralight, current collector and binder-free energy storage device. • Cost-effective device fabrication method. • Excellent electrochemical performance and cycling stability. Development of flexible, ultralight, scalable and non-leaking energy storage devices such as electrochemical capacitors that are on par with commercial standards and offer compliances while retaining safety remain a significant challenge for the realization of wearable devices. Generally, the bottleneck to the improvement of such devices is the need to use ecofriendly electrode and electrolyte materials with desirable surface, electrochemical and mechanical properties. Thus, this study provides a new platform for development of flexible, ultralight, freestanding electrochemical capacitor using a composite of cellulose/SWCNTs (CL/CNTs) electrode films and a new cellulose/NaHSO 4 hydrogel electrolyte. Herein, we took advantage of the renewability and flexibility of cellulose in combination with the high conductivity and storage capacity of SWCNTs to create a high specific capacitance, energy and power density. Moreover, the new cellulose/NaHSO 4 hydrogel electrolyte provided stable cycling, leading to non-leakage device exhibiting ∼100% capacitance retention after 3000 cycles. Cellulosic composites are developed as sustainable free-standing electrode and electrolyte for high performance electrochemical charge storage. [Display omitted] [ABSTRACT FROM AUTHOR]