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Zinc metal, with its high theoretical capacity and low cost, stands out as a promising anode material for affordable high energy-density storage technologies in rechargeable batteries. However, obtaining a high level of reversibility in zinc electrodeposition, which is pivotal for the success of rechargeable zinc-metal-based batteries, remains a significant challenge. A critical factor in this regard is the physicochemical characteristics of the electrolyte solution. Previous studies have indicated that adjusting the electrolyte solutions' composition with additives or co-solvents, along with fine-tuning concentrations and pH levels, can enhance the reversibility and kinetics of Zn deposition/stripping. However, the precise impact of Zn salts counter anions in the electrolyte solutions on these processes is not fully understood yet. Aiming to focus on the key fundamental aspects related to the electrolytes' influences on the Zn electroplating, we delve into the impact of anions on this process. Using advanced in situ and ex situ analytical methods, we reveal the role of the anions in the electrolyte solutions in zinc deposition/dissolution processes. Computational simulations shed light on the electrolytes' solvation structure, establishing a clear relationship between deposition behavior and the molecular variations specific to the different anions. These findings pave the way for new design principles aimed at optimizing the composition of electrolyte solutions for zinc metal batteries, potentially enhancing their performance and efficiency. [ABSTRACT FROM AUTHOR]

Considerable efforts have been invested in replacing standard metallic Zn anodes with diverse conductive substrates in pursuit of higher energy density, durability, and cost-effectiveness in aqueous Zn-based batteries. Despite substantial progress in the development of anode-free Zn systems, there is still a major gap in our fundamental knowledge of how the physicochemical parameters of the substrate (current collector) impact the efficiency of the reversible Zn electrodeposition process. Of particular interest are the interactions between the Zn cations, the accompanied water molecules, and the foreign substrates. As both Zn deposition and hydrogen evolution processes occur at similar potential ranges, the performance of the anode-free cells will be dictated by the catalytic nature of the electrified substrates and the chemistry of their passivation. In this study, we conduct thorough examinations of four prominent current collectors: copper, nickel, titanium, and graphite foils. Using a systematic approach that includes electrochemical investigations supplemented by refined X-ray diffraction analysis and in situ techniques such as online electrochemical mass spectrometry (OEMS) and electrochemical quartz crystal microbalance with dissipation monitoring (EQCM-D), we uncover the critical role of these current collectors in the reversible Zn electroplating process. According to our findings, graphitic foils provide significantly more efficient electrodeposition of Zn in mildly acidic electrolyte solutions. [ABSTRACT FROM AUTHOR]

Digital light processing (DLP) is a vat photopolymerization 3D printing technique with increasingly broad application prospects, particularly in personalized medicine, such as the creation of medical devices. Different resins and printing parameters affect the functionality of these devices. One of the many problems that biomedical implants encounter is inflammation and bacteria growth. For this reason, many studies turn to the addition of antibacterial agents to either the bulk material or as a coating. Zinc oxide nanoparticles (ZnO NPs) have shown desirable properties, including antibacterial activity with negligible toxicity to the human body, allowing their use in a wide range of applications. In this project, we developed a resin of poly(ethylene glycol) diacrylate (PEGDA), a cross-linker known for its excellent mechanical properties and high biocompatibility in a 4:1 weight ratio of monomers to water. The material's mechanical properties (Young's modulus, maximum elongation, and ultimate tensile strength) were found similar to those of human cartilage. Furthermore, the ZnO NPs embedding matrix showed strong antibacterial activity against Escherichia coli (E. coli) and Staphylococcus aureus (S.A.). As the ZnO NPs ratio was changed, only a minor effect on the mechanical properties of the material was observed, whereas strong antibacterial properties against both bacteria were achieved in the case of 1.5 wt.% NPs. [ABSTRACT FROM AUTHOR]

The demand for medical implants has rapidly increased over the last decades. These artificial devices should possess various properties such as biointegration and mechanical characteristics comparable to that of the replaced body parts. Nowadays, orthopedic, dental, and cardiovascular implants consist mainly of metal-based materials. However, metals suffer from poor osseointegration, some are not biocompatible, and some are not corrosion-resistant. Therefore, surface modification is necessary to enhance and improve the overall compatibility. Electrodeposition methods such as electrophoretic and electrochemical deposition are facile approaches for forming homogeneous and multifunctional coatings on conductive and complex geometries. Moreover, electrochemistry enables driving the deposition of nanomaterials and introduce biomolecules and polymers, by which various properties such as antibacterial activity, cell proliferation, and biointegration can be added to the implant surface. This review aims at describing the recent studies involving electrodeposition methods for coatings of medical implants by nanomaterials. [ABSTRACT FROM AUTHOR]

Nanoparticle-imprinted matrices (NAIMs) are an innovative approach for the efficient and selective recognition of nanoparticles (NPs). The NAIM system comprises the preparation of thin films in which NPs are embedded as a template. The removal of the template forms nanometric voids, which are subsequently used for the selective reuptake of NPs identical to those imprinted. The recognition ability depends on several parameters such as the geometrical compatibility between the voids and imprinted NPs, the thickness of the matrix, and the supramolecular interactions between the matrix and the NP capping agents. Herein, we studied carefully the NP–matrix interactions in three NAIM systems, which were prepared by imprinting identical-sized AuNPs, bearing different carboxylic acid-functionalized thiols as capping agents, in a carboxylic acid-functionalized matrix. This experimental setup has enabled us to meticulously examine the selectivity of the NAIM systems driven by matrix–shell interactions. The three studied NAIM systems have shown high and selective reuptake ability once exposed to solutions of NPs stabilized with the same capping agent used for the imprinting process. In particular, the reuptake percentage of the originally imprinted AuNPs ranges from 50 to 80%, whereas the reuptake of AuNPs bearing different carboxylic capping agents than those imprinted was substantially lower (1–11%). Surface-sensitive polarization-modulation infrared reflection-absorption spectroscopy was utilized to correlate the selectivity of the NAIM systems and hydrogen bonding detected between the capping agents and the matrix. This study paves the way for the rational design of NAIM systems, which can be tuned according to the desired shell–matrix interactions and eventually applied in sensing and separation technologies. [ABSTRACT FROM AUTHOR]

The selective recognition of nanoparticles (NPs) can be achieved by nanoparticle-imprinted matrices (NAIMs), where NPs are imprinted in a matrix followed by their removal to form voids that can reuptake the original NPs. The recognition depends on supramolecular interactions between the matrix and the shell of the NPs, as well as on the geometrical suitability of the imprinted voids to accommodate the NPs. Here, gold NPs stabilized with citrate (AuNPs-cit) were preadsorbed onto a conductive surface followed by electrografting of p-aryldiazonium salts (ADS) with different functional groups. The thickness of the matrix was carefully controlled by altering the scan number. The AuNPs-cit were removed by electrochemical dissolution. The recognition of the NAIMs was determined by the reuptake of the original AuNPs-cit by the imprinted voids. We found that the recognition efficiency is a function of the thickness of the NAIM layer and is sensitive to the chemical structure of the matrix. Specifically, a subtle change of the functional group of the p-aryldiazonium building block, which was varied from an ether to an ester, significantly affected the recognition of the NPs. [ABSTRACT FROM AUTHOR]

Speciation of nanoparticles, that is, their differentiation based on size, shape and stabilizing shell is becoming important since their properties depend on these parameters. Nanoparticle-imprinted polymers (NIPs) are a new approach that aims to selectively recognize nanoparticles based on their structural properties. In this study, monolayers of cellulose acetate (CA) accommodating gold nanoparticles stabilized with dodecanethiol (AuNPs/C12) are transferred onto indium tin oxide (ITO) by the Langmuir-Blodgett technique. One to five monolayers are assembled. Electrochemical oxidation dissolves the AuNPs/C12 to form cavities in the films, which fit the size and shape of the AuNPs/C12. Reuptake of the nanoparticles from a solution is successful using the imprinted films, whereas the control films containing only CA layers do not reuptake the AuNPs/C12. The NIPs are highly selective and other gold nanoparticles stabilized by other thiols are not recognized by the imprinted matrix. [ABSTRACT FROM AUTHOR]

The front cover artwork is provided by Prof. Mandler′s group at the Hebrew University (Israel). The image shows the reuptake process in which only the particles with the original shell size are captured by the imprinted cavities, while the others are not recognized. Read the full text of the Article at. [ABSTRACT FROM AUTHOR]