Cationic Effect on the Electrochemical Characteristics of the Hydrothermally Grown Manganese Dioxide

Nanostructured transition metal oxide nanoparticles possess a catalytic activity to hydrogen peroxide. Manganese dioxide particles are one of the promising and available modificators of the electrode surface. Nanostructured MnO2 deposited onto the surface of the electrode enhances the electron transport from the H2O2 molecule to the surface. Thus selectivity and sensitivity of H2O2 detection can be improved. There are a lot of different methods of the impregnation of manganese dioxide particles onto electrode surface. An electrophoretic deposition is one of the most simple and rapid. By adjusting the electrodeposition parameters, particles of different sizes or films can be obtained. A simple and novel hydrogen peroxide sensor based on layer-by-layer assembly of MnO2 nanoparticles and SiO2 film on the ITO electrode was developed. For this purpose MnO2 nanoparticles were electrodeposited on the surface of ITO electrode from MnSO4/CH3COOK solution. The electrochemical characteristics of the modified electrodes were investigated by cyclic voltammetry.The presence of MnO2 on the surface of modified electrode was indicated by the appearance of clear oxidation-reduction peaks of Mn(IV)/Mn(III,II) at E=0.65 V in the electrolyte solution in contrast to unmodified electrode. Optimization of measurement parameters such as the amount of MnO2, applied potential and pH value were studied in details. Under the optimum conditions, the calibration curve for H2O2 determination using modified electrode was linear in the range from 1×10−4 to 1×10−3 mol/dm3 with a detection limit of 0.09×10−4 mol/dm3 (S/N = 3). The linear rang for non-modified electrode was from 1×10−3 to 1×10−2 mol/dm3 with a detection limit of 1.8×10−4 mol/dm3 (S/N = 3). The modified ITO electrode was characterized by higher current than non modified ITO as a result of increasing of electroactive surface area and catalytic effect of electrodeposited MnO2.For the stabilization of MnO2 particles and protection of the electrode surface from impurities, the ITO/MnO2 was covered by thin silica film. The selectivity of H2O2 determination at ITO modified with MnO2/SiO2 was better than at ITO especially in the presence of ascorbic acid which is oxidized at the same potential as H2O2. The oxidation current of ascorbic acid was much higher than H2O2 at nonmodified ITO in contrast to ITO modified with MnO2/SiO2. The developed ITO electrode modified with MnO2/SiO2 is a perspective element of amperometric sensor for the detection of hydrogen peroxide.

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Influence of Ag Doping on the Electrochemical Supercapacitor Characteristics of Manganese Dioxide Prepared by Pulsed Potentiostatic Electrodeposition

Materials Science Forum ◽

10.4028/www.scientific.net/msf.985.147 ◽

2020 ◽

Vol 985 ◽

pp. 147-155

Author(s):

Thi Thanh Bui Huyen ◽

Anh N. Nguyen ◽

Duong T. Nguyen ◽

Thuy Thi Bich Hoang

Keyword(s):

Manganese Dioxide ◽

Electrochemical Impedance ◽

Low Cost ◽

Graphite Substrate ◽

Electrochemical Characteristics ◽

Ag Doping ◽

Cathodic Electrodeposition ◽

Main Compound ◽

Electrochemical Supercapacitor ◽

Charge Discharge

Manganese dioxide (MnO2) is a promising electrode material for electrochemical supercapacitor applications due to its low cost, eco-friendly and high theoretical specific capacitance in a wide potential window. In this study, MnO2 and Ag-doped MnO2 are prepared by cathodic electrodeposition on graphite substrate from electrolyte with the main compound of potassium permanganate using pulse potentiostatic technique. The effect of Ag doping on the morphology, structure and electrochemical properties of MnO2 materials are investigated. Scanning electron microscopy (FESEM), Energy Dispersive X-ray Spectroscopy (EDX), cyclic voltammetry (CV), galvanostatic charge-discharge measurement and electrochemical impedance spectroscopy (EIS) are used for characterization of the prepared materials. The results show that doping Ag into the MnO2 structure has improved electrochemical characteristics of materials. The specific capacitances are calculated for pure MnO2 and Ag-doped MnO2 to be 272.84 and 277.48 F/g, respectively. The prepared materials exhibit the high charge-discharge stability, maintaining at about 92 % for MnO2 and 95 % for Ag-doped MnO2 after 500 cycles of the charge-discharge operation.

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The lithiummanganese dioxide cell IV. Relationship between physicochemical properties and electrochemical characteristics of MnO2 in nonaqueous electrolytes

Journal of Power Sources ◽

10.1016/0378-7753(91)80034-u ◽

1991 ◽

Vol 35 (2) ◽

pp. 175-181 ◽

Cited By ~ 9

Author(s):

N. Ilchev ◽

B. Banov

Keyword(s):

Physicochemical Properties ◽

Manganese Dioxide ◽

Electrochemical Characteristics ◽

Nonaqueous Electrolytes ◽

Lithium Manganese

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STUDY ON LITHIUM MANGANESE OXIDE SPINEL SYSTEM AS CATHODE MATERIALS FOR LITHIUM ION BATTERY: SYNTHESIS, MORPHOLOGICAL AND ELECTROCHEMICAL CHARACTERISTICS

Science and Technology Development Journal ◽

10.32508/stdj.v12i10.2301 ◽

2009 ◽

Vol 12 (10) ◽

pp. 64-71

Author(s):

Binh Thi Xuan Lam ◽

Phung My Loan Le ◽

Thoa Thi Phuong Nguyen

Keyword(s):

Manganese Oxide ◽

Manganese Dioxide ◽

Specific Capacity ◽

Lithium Ion ◽

Lithium Manganese Oxide ◽

Lithium Nitrate ◽

Electrochemical Characteristics ◽

Impregnation Method ◽

Limn2o4 Spinel ◽

Lithium Manganese

Lithium manganese oxide (LiMn2O4) spinel compounds were synthesized by melting impregnation method using manganese dioxide (MnO2) and lithium nitrate (LiNO3). Four sources of MnO2 raw materials were used: a commercial electrochemical manganese dioxide (EMD) supplied by Pin Con O factory; EMD thermal pretreated (EMDt); and MnO2 synthesized chemically (CMD) by oxidation of MnSO4 solution with K2S2O, and EMD synthesized in our laboratory. The effect of the MnO2 materials on the microstructure and electrochemical properties of LiMn2O4 is investigated by X-ray diffraction, scanning electron microscopy, and electrochemical measurements. The charge-discharge cycling behavior in Swagelok model of lithium-ion cells, using synthesized LiMn2O4 as cathode, lithium metal as anode and LiPF6 as electrolyte with Whatman glass separator, showed that the spinels from thermal treated EMDt and CMD gave higher (3100 mAh/g) and more stable values of specific capacity than the spinels from non-treated EMD.

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