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Aqueous zinc-ion batteries (AZiBs) have emerged as a promising alternative to lithium-ion batteries as energy storage systems from renewable sources. Manganese hexacyanoferrate (MnHCF) is a Prussian Blue analogue that exhibits the ability to insert divalent ions such as Zn2+. However, in an aqueous environment, MnHCF presents weak structural stability and suffers from manganese dissolution. In this work, zinc doping is explored as a strategy to provide the structure with higher stability. Thus, through a simple and easy-to-implement approach, it has been possible to improve the stability and capacity retention of the cathode, although at the expense of reducing the specific capacity of the system. By correctly balancing the amount of zinc introduced into the MnHCF it is possible to reach a compromise in which the loss of capacity is not critical, while better cycling stability is obtained. [ABSTRACT FROM AUTHOR]

P'2‐Na0.67Mn0.67Ni0.33O2 (NMNO) is one of the most promising cathodic materials for new generation sodium‐ion batteries (SIBs). One drawback that is preventing its commercialization is however the high instability in the potential window 2.5–4.5 V vs. Na+/Na, caused by degradation reactions affecting the material's structure and composition. Herein we propose a strategy to overcome this weak spot introducing the surface coating of the material particles with inert magnesium oxide, that has been chosen as coating agent because of its low molecular weight. This protective layer is able to reduce the structural instability of the material without modifying the mixed conduction properties and thus globally stabilizing the electrochemical performances. In fact, the electrode of NMNO coated with 7 % of MgO, after an initial stabilization, was able to deliver over 90 mAh g−1 of reversible specific capacity at a current value of 50 mA g−1, with a capacity retention of 70 % after 250 cycles, to be compared with the 30 mAh g−1 of the uncoated material. The effect of the coating on the particles surface is here investigated with differential electrochemical mass spectrometry, to analyze the influence of the treatment on the electrode/electrolyte interphase. [ABSTRACT FROM AUTHOR]

In recent years, much effort has been invested into developing multifunctional drug delivery systems to overcome the drawbacks of conventional carriers. Magnetic nanoparticles are not generally used as carriers but can be functionalised with several different biomolecules and their size can be tailored to present a hyperthermia response, allowing for the design of multifunctional systems which can be active in therapies. In this work, we have designed a drug carrier nanosystem based on Fe3O4 nanoparticles with large heating power and 4-amino-2-pentylselenoquinazoline as an attached drug that exhibits oxidative properties and high selectivity against a variety of cancer malignant cells. For this propose, two samples composed of homogeneous Fe3O4 nanoparticles (NPs) with different sizes, shapes, and magnetic properties have been synthesised and characterised. The surface modification of the prepared Fe3O4 nanoparticles has been developed using copolymers composed of poly(ethylene-alt-maleic anhydride), dodecylamine, polyethylene glycol and the drug 4-amino-2-pentylselenoquinazoline. The obtained nanosystems were properly characterised. Their in vitro efficacy in colon cancer cells and as magnetic hyperthermia inductors was analysed, thereby leaving the door open for their potential application as multimodal agents. [ABSTRACT FROM AUTHOR]

This document is a correction notice for a scientific paper titled "Ionic Liquid-Laden Zn-MOF-74-Based Solid-State Electrolyte for Sodium Batteries." The authors have identified an error in Table 1 of the original publication, where the superscripts of the conductivity values were written incorrectly. The corrected table has been provided, and the authors state that this correction does not affect the scientific conclusions of the paper. The original publication has been updated to reflect this correction. [Extracted from the article]

An alternative anodeto metallic sodium based on the high capacity of Sn4P3 alloy is investigated for the first time in Na–O2 batteries. This alloy is synthesised by an easy and scalable method based on ball milling which is further optimized in order to obtain the most suitable morphology while avoiding agglomeration of the material. First, the stability of Sn4P3/C composite within the battery environment is analysed and compared to that of metallic Na. Second, the electrochemical study reveals the formation of sodium superoxide on both the metallic anode and Sn4P3 alloy for the first time, which evidences the existence of O2/O2− crossover processes. Complementary impedance studies, at various voltages and as a function of cycle number, demonstrate a higher stability of the solid electrolyte interphase (SEI) throughout cycling in addition to presenting lower reactivity and greater stability than the metallic Na system. Regarding the cycling performance, although it is lower than that of metallic Na, it surpasses that exhibited by other alternative anodes under similar conditions. This work therefore demonstrates the viability of a new family of anodes, paving the way for the development of more stable and safer Na–O2 batteries. Moreover, the importance of oxygen crossover is highlighted which is a common problem regardless of the anode used. [ABSTRACT FROM AUTHOR]

Due to the increase in global energy demand and the unsustainability of burning fossil fuels, the search for optimized energy systems has become a priority in recent years. In 1990, lithium batteries revolutionized the energy market; however, the unceasing increase in demand and the limited lithium supplies induce the need for alternative energy storage systems. Li–O2 batteries are promising to make a difference in applications such as those related to electromobility. In the last few years the interest in metal–air batteries has increased exponentially; however, several challenges must be overcome to improve their efficiency. For this system to be viable, it is necessary to solve key problems such as the high polarization of the charge reaction. To overcome this limitation, facilitate the oxidation of the Li2O2 discharge product, and increase the efficiency of these batteries, the use of redox mediators has been widely investigated. In the present work, the mediators reported in the Li–O2 literature are classified into four groups according to their charge state in both their reduced and oxidized forms and their performance is discussed. Finally, a summary of the redox mediators used in analogous Na–O2 batteries is presented. This work provides a clear view about the use of redox mediators as a powerful strategy for the commercialization of these metal–O2 batteries, discussing the advantages and disadvantages of this type of homogenous catalyst, and suggesting future directions. [ABSTRACT FROM AUTHOR]

A new route to enhance the performance of Na–O2 cells is demonstrated. Redox mediators (such as ethyl viologen) are shown to facilitate the discharge reaction, producing an increased capacity (due to suppressed electrode passivation), higher discharge potential (due to faster kinetics) and stable cycling. [ABSTRACT FROM AUTHOR]