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Aqueous zinc‐ion batteries (AZIBs) have become a promising energy storage device due to their low cost and high security. However, the severe dendrite growth and side reactions on metallic zinc (Zn) anode hamper their commercial implementation. Herein, a strongly electronegative trifluoroborate anion (─BF3−) functionalized polyacrylamide hydrogel (PAME) is well‐designed and constructed as the quasi‐solid‐state electrolyte to overcome these obstacles. The PAME chain segments terminated with strongly polar functional groups promote the conversion of water molecules from free water to bound water through the enhanced hydrogen bonding interaction to alleviate the side reactions. Furthermore, the PAME electrolyte featured with hierarchically porous structure and enhanced electrostatic interaction among the ─BF3− groups, and Zn2+ ions homogenizes the high‐flux Zn ion transport and induce the uniform deposition to restrain dendrite growth. Consequently, the assembled Zn‖PAME‖Zn batteries deliver remarkable cycling stability over 1800 h at 1 mA cm−2 and 900 h at 15 mA cm−2. Additionally, the constructed Zn‖PAME‖MnO2 full cells achieve a reversible capacity of 202 mAh g−1 at 2.0 A g−1 with a capacity retention rate of 91.4% over 500 cycles. This work sheds light on constructing the strongly polar hydrogel electrolyte to boost free‐dendrite Zn anodes for long‐lifespan AZIBs. [ABSTRACT FROM AUTHOR]

In the quest for sustainable energy storage technologies, lithium‐based batteries, despite their prominence, face limitations such as high costs, safety risks, and supply chain issues. This has propelled the exploration of alternative materials, with aqueous aluminum‐ion batteries (AAIBs) emerging as a promising candidate due to their high energy density, abundance, and cost‐effectiveness. However, the low equilibrium reduction potential of aluminum ions presents significant challenges, including hydrogen evolution and poor cyclability. Addressing these, the study pioneers the application of single‐atom catalysts (SACs) in AAIBs, leveraging their high atom utilization and stability to enhance aluminum deposition and suppress hydrogen evolution. Sn, In, Cu, and Ni SACs are evaluated through density functional theory analysis and experimental validation, with Sn SAC identified as the most effective. Subsequently, the Sn SAC based anode demonstrates enhanced performance, achieving stable cycling over 500 h at 0.5 mA cm−2, significantly improved capacity retention (60 mAh g−1@300 cycles), and rate performance (50 mAh g−1@1 A g−1) in full cell tests. This work underscores the potential of SACs in advancing AAIB technology and opens new pathways for energy storage solutions. [ABSTRACT FROM AUTHOR]

The influence of temperature on the properties of nanocrystalline Co–W coatings obtained from a citrate electrolyte at pH 6.7 and deposited under natural convection conditions was studied. The influence of the electrolyte temperature on the morphology, composition, structure, and roughness of coatings, as well as their corrosion and tribological properties, is demonstrated. It is shown that the structure of the coating can change from the X-ray amorphous to the crystalline one when the deposition temperature of the coating is increased to 90°С. The average value of the mass wear of Cо–W coatings formed at 80°С and measured under the linear friction condition of 0.08 mg is 62 times lower than that of a Cr coating (4.95 mg) and 84 times lower that at the surface of steel SK-5 (6.71 mg). When testing by the reciprocating wear method, the value of the volumetric wear of Co–W coatings obtained in the 50–70°С temperature range was 0.00109 mm3, which is 55 times lower than the wear value of a Cr coating (0.0596 mm3) and 41 times lower than that of the steel SK-5 surface (0.0449 mm3). The paper also shows a slight decrease in the currents of corrosion coatings and a decrease in the dispersion values of the corrosion potentials obtained after mechanical polishing of the surface of the coatings at temperatures in the range of 20–90°С. Under the corrosive effect of 3.5% sodium chloride, an increase in the deposition temperature of the coating is accompanied by a slight increase in the corrosion current. [ABSTRACT FROM AUTHOR]

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Li metal exhibits high potential as an anode material for next-generation high-energy density batteries. However, the nonuniform transport of Li + ions causes Li-dendrite growth at the metal electrode, leading to severe capacity decay and a short cycling life. In this study, negatively charged lithiophilic sites (such as cationic metal vacancies) were used as hosts to regulate the atomic-scale Li + -ion deposition in Li-metal batteries (LMBs). As a proof of concept, three-dimensional (3D) carbon nanofibers (CNFs) decorated with negatively charged TiNbO 4 grains (labeled CNF/nc-TNO) were confirmed to be promising Li hosts. Cationic vacancies caused by the carbothermal reduction of Nb 5+ and Ti 4+ ions generated a negatively charged fiber surface and strong electrostatic interactions that guided the Li + -ion flux to the shadowed areas underneath the fiber and throughout the fibrous mat. Consequently, circumferential Li-metal plating was observed in the CNF/nc-TNO host, even at a high current density of 10 mA cm -2 . Moreover, CNF/nc-TNO asymmetric cells delivered a significantly more robust and stable Coulombic efficiency (CE) (99.2% over 380 cycles) than cells comprising electrically neutral CNFs without cationic defects (which exhibits rapid failure after 20 cycles) or Cu foil (which exhibits rapid CE decay, with a CE of 87.1% after 100 cycles). Additionally, CNF/nc-TNO exhibited high stability and low-voltage hysteresis during repeated Li plating/stripping (for over 4000 h at 2 mA cm -2 ) with an areal capacity of 2 mAh cm -2 . It was further paired with high-voltage LiNi 0.8 Co 0.1 Mn 0.1 (NCM811) cathodes, and the full cells showed long-term cycling (220 cycles) with a CE of 99.2% and a steady rate capability.

The electrodeposition of Fe-Mo alloys from an alkaline solution containing sorbitol as the complexing agent for Fe(III) ions was studied. XRD analysis of the film produced by reduction of [MoO 4 ] 2- anions at a copper substrate showed the formation of MoO 2 . The presence of the intermediate Fe(II) species was detected by electrolysis from an Fe-Mo solution and Visible spectroscopy of the final solution in the presence of 1,10-phenanthroline. The Visible spectrum showed a broad absorption ( λ max  = 514 nm) typical of the [Fe(phen) 3 ] 2+ complex. Under our conditions, the Fe-Mo alloy was formed from reduction of [Fe(OH) 2 (C 6 H 12 O 6 ) 2 ] 3- to [Fe(OH) 2 (C 6 H 12 O 6 ) 2 ] 4- , reduction of [MoO 4 ] 2- to molybdenum (IV) oxide/hydroxide and its further reduction to Mo 0 concomitant with [Fe(OH) 2 (C 6 H 12 O 6 ) 2 ] 4− ads to Fe 0 . Photomicrographs of the Fe-Mo electrodeposits produced with q d 5.30Ccm −2 showed that they were smooth or contained cracks, depending on the deposition potential (E d ). Chemical composition analysis by EDXS of Fe-Mo electrodeposits (q d 5.30Ccm −2 ) showed that deposits containing 5.5 at% (18.8 wt%) Mo could be produced at E d −1.40 V and similar values were obtained at more negative potentials. X-Ray diffraction indicated that the Fe-Mo coatings were composed of Fe 3 Mo and Fe 2 MoO 4 phases, regardless of E d . The presence of the Fe 2 MoO 4 phase on the sample surface could explain the observation of Fe 2+ and Mo 4+ states by XPS, although the occurrence of others crystalline oxide phases, such as FeMoO 4 and Fe 2 (MoO 4 ) 3 could not be discarded. The crystal size value varied from ∼47 nm to ∼37 nm, when E d changed to more negative values. [ABSTRACT FROM AUTHOR]

• The reduction potential of Sn, Ag and Cu was narrowed by the 1ChCl: 2EG DES system to achieve the co-deposition of ternary alloy solderable coating. • The results showed that the composition and crystal structure of Sn-Ag-Cu ternary alloy solderable coating can be controlled by adjusting the deposition potential. • From the 1ChCl: 2EG DES system, we obtained a Sn-Ag-Cu ternary alloy solderable coating with a melting point of 215.02 °C by electrodeposition methods. Ternary Sn-Ag-Cu solderable alloy coatings were electrodeposited using deep eutectic solvent-based electrolytes, at different deposition potentials. The obtained deposits have been characterized from surface morphology, composition, crystalline grain and phase via Scanning Electron Microscopy (SEM) associated with Energy Dispersive X-ray spectroscopy (EDX) and X-ray diffraction (XRD). To get information on the alloy melting point, Differential Scanning Calorimetry (DSC) has been involved. The results showed that the crystalline grain became finer and the coating became denser as the deposition potential increased. In addition, the presence of Cu 6 Sn 5 phase is facilitated by more cathodic deposition potentials while the Ag 3 Sn phase was evidenced at lower potential values. The value of the melting point of Sn-Ag-Cu alloy (Sn90.9-Ag7.6-Cu1.5) deposited at potentials of −1.2 V was of 215.02 ℃. Based on the results obtained during the analysis of the current–time curves using the Scharifker-Hills' model, it has been found that both single metal and alloy deposition processes correspond to a nucleation and tridimensional growth controlled by diffusion. The deposition processes of Sn and Ag are conducted by an instantaneous mechanism, while in the case of Cu, a progressive one has been determined. The deposition process of Sn-Ag-Cu alloy showed a deviation from the instantaneous nucleation. [ABSTRACT FROM AUTHOR]

Abstract: FEBIP –focused electron beam induced processing- is a novel technology which renders outstanding advantages compared to other miniaturization techniques, like electron beam lithography, deep X-ray lithography, or 3D construction by optical polymerization. The principle, process characteristics, outstanding results and a variety of possible applications is described. [Copyright &y& Elsevier]

Abstract: “Micelle-enhanced” polyelectrolyte capsules were fabricated via a layer-by-layer technique, templated on hybrid calcium carbonate particles with built-in polymeric micelles based on polystyrene-b-poly(acrylic acid). Due to the presence of a large number of negatively charged micelles inside the polyelectrolyte capsule, which were liberated from templates, the capsule wall was reconstructed and had properties different to those of conventional polyelectrolyte capsules. This type of capsule could selectively entrap positively charged water-soluble substances. The encapsulation efficiency of positively charged substances was dependent on their molecular weight or size. For some positively charged compounds, such as rhodamine B and lysozyme, the concentration in the capsules was orders of magnitude higher than that in the incubation solution. In addition, in vitro release study suggested that the encapsulated compounds could be released through a sustained manner to a certain degree. All these results point to the fact that these capsules might be used as novel delivery systems for some water-soluble compounds. [Copyright &y& Elsevier]

Abstract: Molybdenum oxides have been produced by electrodeposition in sulphate medium from solutions containing molybdate, in the presence or in the absence of citrate, Co(II) and Co(II)+Ni(II). The goal of this work was the characterisation of intermediate molybdenum oxides able to progress to Co–Mo and/or Co–Ni–Mo electrodeposits. For this purpose, several oxide layers were prepared on ITO/glass and silicon-based substrates and characterised by UV–Vis, X-ray photoelectron spectroscopy and X-ray diffraction. The kind of molybdenum oxides that would evolve to the alloy presented a mixed valence state of MoIV and MoV and a certain degree of crystallinity. A yellow-brown-coloured film was observed when a continuous oxide layer was electrodeposited. Inclusion of small amounts of Co or Co+Ni occurred during oxide formation, thereby leading to doped molybdenum oxide layers. There would be two factors that determine the viability of the alloy deposition: the formation of reasonably reduced molybdenum oxides and the interaction between citrate and the other metals (cobalt, nickel) in solution. These requirements would be satisfied at solution pH>2. [Copyright &y& Elsevier]

Metallic lithium (Li), with its high capacity and low redox potential, shows significant development potential for high-energy-density Li batteries. Unfortunately, huge volumetric changes, uncontrollable Li dendrites, and interfacial parasitic reactions limit its commercial application. Herein, we demonstrate a rational strategy of encapsulating metallic Li into the interior spaces of hollow carbon (C) nanocages for dendrite-free Li metal anodes. We find that the poly(vinylidene difluoride)-binder-modified thin-layer C walls on the C nanocages can guide Li deposition into the interior spaces of these hollow C nanocages and simultaneously reduce the interfacial parasitic reactions between deposited Li metal and an electrolyte. In addition, because of the high specific surface area and huge interior spaces of the C nanocages, the local current density can be reduced and large volume changes are mitigated. Specifically, this electrode exhibits negligible volume changes at 1.0 mAh/cm 2 and a 14.9% volume change at 3.0 mAh/cm 2 . The copper (Cu) foil electrode exhibits 87.9% and 234.3% volume changes at the corresponding deposition capacities. Consequently, a C-nanocage-modified electrode exhibits an outstanding Coulombic efficiency of 99.7% for nearly 150 cycles at a current density of 1.0 mA/cm 2 , while a Cu foil electrode exhibits less than a 70.0% Coulombic efficiency after only 43 cycles. When paired with a sulfur cathode, the C-nanocage-modified electrode exhibits better cycling and rate performances than the pristine Cu foil electrode.