Properties Of Manganese Dioxide Research Articles

A novel Ni3S2/MnO2@N,F-CQDs composite with spherical-chain-like morphology for efficient oxygen evolution reaction in aqueous alkaline solutions

Developing earth-abundant transition metal-based oxygen evolution reaction (OER) electrocatalysts is extremely essential for accomplishing efficient electrocatalytic overall water splitting. Herein, we synthesized a Ni3S2/MnO2@N,F-CQDs catalyst with a microstructure composed of interlaced nanowires in a spherical-chain shape by treating a nickel foam substrate with sulfur and co-regulating the morphology and properties of manganese dioxide with carbon dots. The catalyst exhibited excellent OER electrocatalytic performance and stability under alkaline conditions, requiring only a low overpotential of 226 mV at 10 mA cm-2 and a Tafel slope of 105.76 mV dec-1. Furthermore, the catalyst remained stable after 3000 cycles of Cyclic Voltammetry (CV) testing and multistep chronopotentiometric (CP) measurements at the current density of 10, 50 and 100 mA cm−2 for 12 h, respectively. The enhanced performance of Ni3S2/MnO2@N,F-CQDs catalyst was mainly attributed to the practical improvement of charge interface transport performance induced by carbon dots and interface layer Ni3S2 which increased active catalytic sites of the electrode and reduced charge transfer resistance. These results suggest a promising approach for developing efficient OER electrocatalysts.

Comprehensive study to ascertain the effect of MnO2 loading on supercapacitive properties of conducting polymers

This study reports the electrochemical properties of Manganese dioxide (MnO2) with four types of conducting polymers such as polyaniline (PANi), polythiophene (PTh), polypyyrole, and polyindole (PIn) by preparing their composites. All four conducting polymers were prepared by chemical oxidative polymerization approach. The prepared composites were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), Raman spectroscopy, ultra–violate visible (UV–VIS) spectroscopy, and photoluminance (PL). Similarly, the supercapacitive properties such, cyclic voltammetry (CV) curve, capacitance retention and cycle stability of composite materials were investigated. The highest value of specific capacitance was obtained for MnO2-PANi (Mn-PANi) composite, which was found to be 633.75 Fg−1.

The Experimental Study of the Adsorption Behavior of Cd on Manganese Dioxides

This paper studied the adsorption behavior of Cd on manganese dioxide, focusing on the factors of affecting the adsorption. The results showed that the adsorption equilibrium was reached in about six hours. The amount of manganese dioxide adsorption of cadmium ions increased with the increasing of the initial Cd2+ concentration, and then decreased, adsorption isotherms accorded with Langmuir isotherm equation. The most influence factor on the adsorption properties of manganese dioxide was pH value. After the addition of inorganic salts, only ammonium bicarbonate could promote the adsorption of cadmium, other inorganic salts inhibited the adsorption of cadmium.

Effect of physical and chemical properties of manganese dioxide on the oxidative decomposition of formaldehyde at room temperature

Effect of physical and chemical properties of manganese dioxide on the oxidative decomposition of formaldehyde at room temperature

Preparation and properties of manganese dioxide studied by QCM

Electrodeposition and cycling of MnO2 was tested by cyclic voltammetry and electrochemical quartz crystal microbalance (QCM). The electrodeposition from manganese sulfate and the material cycling are accompanied by strong and almost reversible water sorption close to the stoichiometric ratio 3:1. Similar reversible sorption of water was observed also on solid MnO2 deposited as an “ink” (slurry) with PTFE as a binder on the QCM probe.

Corrosion and adsorption properties of electrochemical manganese dioxide in the acidic and weakly alkaline sulfate solutions

Corrosion and adsorption properties of manganese dioxide, which was anodically deposited on platinum, its powder, and compacted tablets of manganese dioxide in the solutions with various pH values are studied using various experimental methods. It is shown that the corrosion rate of manganese dioxide decreases with increasing pH of solution, and the process proceeds by the electrochemical mechanism with conjugate chemical reactions of the formation and decomposition of the product of transition stage. The adsorption properties of manganese dioxide powder with respect to copper ions increase with increasing pH of solution, whereas the amount of manganese ions passing to the solution almost vanishes at pH 9.