Sensitive Hydrazine Detection Using a Porous Mn2O3 Nanofibers-Based Sensor

Coupling of Mn2O3 with Heteroatom-Doped Reduced Graphene Oxide Aerogels with Improved Electrochemical Performances for Sodium-Ion Batteries

Currently, efforts to address the energy needs of large-scale power applications have expedited the development of sodium-ion (Na-ion) batteries. Transition-metal oxides, including Mn₂O₃, are promising for low-cost, eco-friendly energy storage/conversion. Due to its high theoretical capacity, Mn₂O₃ is worth exploring as an anode material for Na-ion batteries; however, its actual application is constrained by low electrical conductivity and capacity fading. Herein, we attempt to overcome the problems related to Mn₂O₃ with heteroatom-doped reduced graphene oxide (rGO) aerogels synthesised via the hydrothermal method with a subsequent freeze-drying process. The cubic Mn₂O₃ particles with an average size of 0.5-1.5 µm are distributed to both sides of heteroatom-doped rGO aerogels layers. Results indicate that heteroatom-doped rGO aerogels may serve as an efficient ion transport channel for electrolyte ion transport in Mn₂O₃. After 100 cycles, the electrodes retained their capacities of 242, 325, and 277 mAh g^-1, for Mn₂O₃/rGO, Mn₂O₃/nitrogen-rGO, and Mn₂O₃/nitrogen, sulphur-rGO aerogels, respectively. Doping Mn₂O₃ with heteroatom-doped rGO aerogels increased its electrical conductivity and buffered volume change during charge/discharge, resulting in high capacity and stable cycling performance. The synergistic effects of heteroatom doping and the three-dimensional porous structure network of rGO aerogels are responsible for their excellent electrochemical performances.

Soft-template-assisted synthesis: a promising approach for the fabrication of transition metal oxides

The past few decades have witnessed transition metal oxides (TMOs) as promising candidates for a plethora of applications in numerous fields. The exceptional properties retained by these materials have rendered them of paramount emphasis as functional materials. Thus, the controlled and scalable synthesis of transition metal oxides with desired properties has received enormous attention. Out of different top-down and bottom-up approaches, template-assisted synthesis predominates as an adept approach for the facile synthesis of transition metal oxides, owing to its phenomenal ability for morphological and physicochemical tuning. This review presents a comprehensive examination of the recent advances in the soft-template-assisted synthesis of TMOs, focusing on the morphological and physicochemical tuning aided by different soft-templates. The promising applications of TMOs are explained in detail, emphasizing those with excellent performances.

Room-temperature synthesis of a new stable (N2H4)WO3 compound: a route for hydrazine trapping

A new (N₂H₄)WO₃ compound has been obtained by mixing WO₃ and aqueous hydrazine solution at room temperature for 24 h. The reaction is catalyzed by the presence of lithium. X-ray, synchrotron and neutron diffraction techniques have shown that the material crystallizes in trigonal space group P3₂21 (No. 154). Chains of distorted WO₄ tetrahedra extend along the a axis of the unit cell, linked by a corner-sharing oxygen atom: the N₂H₄ are in the voids between them. The thermal characterization shows that this new compound is stable up to 220°C, greatly beyond the boiling point of N₂H₄ (114°C); thus making it a promising candidate for catalysis or trapping applications.

Manganese dioxide–vulcan carbon@silver nanocomposites for the application of highly sensitive and selective hydrazine sensors

Active carbon supported MnO₂@Ag nanocomposites were developed for the highly sensitive and selective electrochemical detection of hydrazine.

Facile Fabrication of Mn2O3 Nanoparticle-Assembled Hierarchical Hollow Spheres and Their Sensing for Hydrogen Peroxide

In the present work, we described the facile hydrothermal fabrication of Mn2O3 nanoparticle-assembled hierarchical hollow spheres and their application for the electrochemical determination of hydrogen peroxide (H2O2). The composition and morphology of the as-prepared samples were well characterized by powder X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS). Because of the electrochemical responses toward H2O2, a novel nonenzymatic electrochemical sensor for the H2O2 determination based on Mn2O3 hollow spheres modified glassy carbon electrode was proposed. The electrochemical properties of the modified electrode were investigated by cyclic voltammetry, electrochemical impedance spectroscopy and chronoamperometry. The modified electrode displayed distinct amperometric response to H2O2 in a wide concentration range 0.10-1276.5 μM, with a linear range of 0.10-126.5 μM and a detection limit of 0.07 μM (S/N = 3). It exhibited excellent analytical performance in terms of long-time stability, good reproducibility and acceptable anti-interference ability. In addition, it was applied for the H2O2 determination in real samples directly with acceptable accuracy and recovery, demonstrating its potential application in routine H2O2 analysis.

Rapid oxidative degradation of methylene blue by various metal oxides doped with vanadium

The oxidative degradation of methylene blue in the presence of various metal oxides doped with vanadium was studied.

Catalytic activity of MnOx/WO3 nanoparticles: synthesis, structure characterization and oxidative degradation of methylene blue

MnO_x/WO₃ nanoparticles were found to be an effective catalyst for the degradation of methylene blue, an important industrial dye and a problematic pollutant.