Influence of the solution pH on the nanostructural, and electrochemical performance of electrolytic manganese dioxide

Functionalized Electrolytic Manganese Dioxide Nanostructure Prepared at Fixed pH for Electrochemical Supercapacitor

“…It was confirmed that ␣-MnO 2 was produced at lower pH. 6 M5, in addition to the pure phases, consists of ␤-MnO 2 . This is observed by a shift in the peak at 2 Ϸ 22°to a higher angle and a sharper peak at 2 Ϸ 56°.…”

“…[1][2][3][4][5] It is used especially as an electrode material in batteries and supercapacitors because of its energetic compatibility in a reversible electrochemical system. [4][5][6][7] Electrolytic manganese dioxide ͑EMD͒ can be produced by an electrolysis of an aqueous solution of MnSO 4 . The electrodeposition of EMD is overlapped by the oxidation ͑Reaction 1͒ and reduction ͑Reaction 2͒ of species on the anode and the cathode, respectively 5,6 Mn 2+ + 2H 2 O → MnO 2 + 4H + + 2e − anodic reaction ͓1͔ 2H + + 2e − → H 2 cathodic reaction ͓2͔…”

“…It leads to a large decrease in the pH value and to a change in the electrodeposition conditions and the properties of EMD deposits. 6,7 In a previous paper, we adjusted the pH at 2 and 5 and then characterized the samples. The results confirmed that the pH of the solution has remarkable effects on the nanostructure, crystal structure, porosity, and the electrochemical performance of the EMD as a cathode in rechargeable alkaline manganese dioxide batteries.…”

The energy saving mechanism of gas diffusion electrode based on Pt/C catalyst for saving energy and green electrodeposition of manganese dioxide

“…The theoretical potential of the ORR at the Pt/C GDE is 1.23 V [4], however, the theoretical potential of hydrogen evolution reaction is only 0 V [5]. So the theoretical cell voltage of the Pt/C GDE is 1.23 V [6] lower than traditional electrode.…”

Rechargeability improvement of δ-type chemical manganese dioxide with the co-doping of Bi and Ni in alkaline electrolyte

“…Adelkhani et al found that the cycle life of the pulse current deposited electrolytic manganese dioxide (EMD) was nearly 230 cycles; on the contrary, the life of the direct current deposited one did not exceed 20 cycles [6]. They also revealed that a/g-type EMD electrodeposited at pH 2 exhibited good electrochemical performances and a-type EMD displayed very stable cycling behavior [7].…”