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We synthesize Sb/Sb2O3 nanoparticles by the oxidation of Sb nanoparticles at 100, 200, and 300 °C. The half sodium-ion batteries with Sb/Sb2O3-200 exhibit the optimal performance with a charge capacity of 540 mAh g−1 after 100 cycles at 0.1 A g−1, maintaining up to six times more capacity than pure Sb, and superior rate performance with 95.7% retention after cycling at varied current densities. One reason for this is that Sb/Sb2O3-200 is at exactly the optimum ratio of Sb2O3:Sb and the particle size of Sb/Sb2O3 to ensure both high capacity for Na+ and small stress during sodiation/desodiation, which is confirmed by the diffusion–stress coupled results. It indicates that increasing the ratio of Sb2O3:Sb causes a decrease of Mises equivalent stress, radial stress, and tangential stress in the range of 1:1–3.5:1, and an increase in the range of 3.5:1–4:1. These stresses decrease with a particle radius in the range of 30–50 nm and increase with a particle radius in the range of 50–70 nm. Additionally, another reason is related to the formation of cycling-induced coral-like Sb, which can promote Na+ diffusion, relieve cycling-induced volume changes, and provide exceptional Na+ storage. [ABSTRACT FROM AUTHOR]

In the present research, a nonenzymatic glucose biosensor was fabricated by depositing Ag nanoparticles (Ag-NPs) using in situ chemical reduction method on TiO2 nanotubes which were synthesized by anodic oxidation process. The structure, morphology, and mechanical behaviors of electrode were examined by scanning electron microscopy and nanoindentation. It was found that Ag-NPs remained both inside and outside of TiO2 nanotubes whose length and diameter were about 1.2 μm and 120 nm. The composition was constructed as an electrode of nonenzymatic biosensor for glucose oxidation. The electrocatalytic properties of the prepared electrodes for glucose oxidation were investigated by cyclic voltammetry (CVs) and differential pulse voltammetry (DPV). Compared with bare TiO2 and Ag-fresh TiO2 nanotube, Ag-TiO2/(500°C) nanotube exhibited the best electrochemical properties from cyclic voltammetry (CVs) results. Differential pulse voltammetry (DPV) results showed that, at +0.03 V, the sensitivity of the electrode to glucose oxidation was 3.69 mA⁎cm-2⁎mM-1 with a linear range from 20 mM to 190 mM and detection limit of 24 μM (signal-to-voice ratio of 3). In addition the nonenzymatic glucose sensors exhibited excellent selectivity, stability, and repeatability. [ABSTRACT FROM AUTHOR]

Lithium-ion batteries (LIBs) have dominated the portable electronic and electrochemical energy markets since their commercialisation, whose high cost and lithium scarcity have prompted the development of other alkali-ion batteries (AIBs) including sodium-ion batteries (SIBs) and potassium-ion batteries (PIBs). Owing to larger ion sizes of Na + and K + compared with Li + , nanocomposites with excellent crystallinity orientation and well-developed porosity show unprecedented potential for advanced lithium/sodium/potassium storage. With enticing open rigid framework structures, Prussian blue analogues (PBAs) remain promising self-sacrificial templates for the preparation of various nanocomposites, whose appeal originates from the well-retained porous structures and exceptional electrochemical activities after thermal decomposition. This review focuses on the recent progress of PBA-derived nanocomposites from their fabrication, lithium/sodium/potassium storage mechanism, and applications in AIBs (LIBs, SIBs, and PIBs). To distinguish various PBA derivatives, the working mechanism and applications of PBA-templated metal oxides, metal chalcogenides, metal phosphides, and other nanocomposites are systematically evaluated, facilitating the establishment of a structure-activity correlation for these materials. Based on the fruitful achievements of PBA-derived nanocomposites, perspectives for their future development are envisioned, aiming to narrow down the gap between laboratory study and industrial reality., (© 2024. The Author(s).)

A novel γ-MnO 2 /carbon nanofiber composite electrode material with a morning glory structure was prepared for the first time by electrospinning a mixture solution of Mn(CH 3 COO) 2 salt and polyacrylonitrile and subsequently treating it with NH 3 atmosphere. The resultant materials were applied in supercapacitors, exhibiting a high voltage of 2 V and high energy density of 15.7 W h kg -1 at the current density of 0.5 A g -1 in 1 M Na 2 SO 4 solution. In this study, precisely controlling the concentration and time of the reaction resulted in the novel morning glory structure. And the morning glory structure at the surface of the carbon nanofibers increased the specific surface area and shortened the diffusion path for charge transport, increasing the Na + /H + ion intercalation capacity, accounting for the high voltage and energy density of the present supercapacitors. These results demonstrated that this new-type of carbon nanofiber with morning glory structure electrode material is potentially superior in obtaining a high voltage for electrode materials and supercapacitors. We hope that these novel materials can expand to different applications in the energy or catalytic field., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)