λ-MnO2, a metastable form of manganese dioxide, retains the cubic spinel structure upon lithium removal from LiMn2O4 by soft chemical methods, either electrochemical or acid leaching. The minimum lithium content, achieved by the latter route at pH 1, is Li0.10MnO2, which is in reasonable agreement with previous reports. For lithium contents near the minimum value, long-range antiferromagnetic o...

In situ measurements of the hydrothermal formation of LiMn2O4 (LMO) nanocrystallites reveal that the reaction progresses in steps, each creating a different crystalline phase. The reaction route is summarized as KMnO4→disordered δ-MnO2→(ordered δ-MnO2)→LiMn2O4→(γ-Mn2O3)→Mn3O4. The phase purity of LMO can be controlled by reaction time and temperature where phase pure LMO is obtained after 150-2...

Gradient Mn-La-Pt catalysts with three-layered structure of manganese dioxide (MnO2), lanthanum oxide (La2O3), and Platinum (Pt) for Li-O2 battery are prepared in this study. The mass ratio of the catalysts is respectively 5:2:3, 4:2:4, and 3:2:5 (MnO2: La2O3: Pt) which is start from the side of the electrolyte. The relationship between morphology structure and electrochemical performance of gr...

In this scientific research, MnO2 nanoparticles (NPs) have been successfully prepared by a precipitation method using KMnO4, MnSO4.H2O and H2O2 (30%) as the precursors. As-prepared sample was identified by X-ray diffraction (XRD), Scanning electron microscopy (SEM), Transmission electron microscopy (TEM) and Infrared (IR) techniques. The transmission electron microscopy (TEM) showed 7-8 nm rang...

Free-standing NiO/MnO2 core-shell nanoflake structure was deposited on flexible carbon cloth (CC) used as electrode for high-performance supercapacitor (SC). The NiO core was grown directly on CC by hydrothermal process and the following annealing treatment. MnO2 thin film was then covered on NiO structures via a self-limiting process in aqueous solution of 0.5 M KMnO4 and 0.5 M Na2SO4 with a c...

In recent years, thin, lightweight and flexible solid supercapacitors are of considerable interest as energy storage devices. Here we demonstrated all-solid supercapacitors (SSCs) with high electrochemical properties, low self-discharge characteristics based on manganese dioxide/polyaniline (MNW/PANI) coaxial nanowire networks. The synergistic effect of MnO2/PANI plus the unique coaxial nanostr...

On the catalyst surface, crystal facets with different surface atom arrangements and diverse physicochemical properties lead to distinct catalytic activity. Acquiring a highly reactive facet through regulation is an efficient strategy promote oxidative decomposition of wastewater organic pollutants via peroxymonosulfate (PMS) activation. However, mechanism which affect PMS activation still uncl...

In this report, the synergetic sonoelectrochemical method was utilized to produce magnetite nanoparticles doped with MnO2 assistance of ultrasound form nanoarchitectonic magnetic crystals a mesoporous @ manganese dioxide (m-Fe3O4@MnO2) hybrid nanostructure. The nanocomposite rapidly produced based on nucleation and growth pure iron-oxide nanocrystals in electrochemical system. pure, highly amor...

Electrochemical performance and production cost are the main concerns for the practical application of supercapacitors. Here we report a simple and universally applicable method to prepare hybrid metal oxides by metal redox reaction utilizing the inherent reducibility of metals and oxidbility of for the first time. As an example, Ni(OH)2/MnO2 hybrid nanosheets (NMNSs) are grown for supercapacit...