Effects of reaction parameters on the electrochemical formation of multilayer films composed of manganese oxides and tetra-alkylammonium ions

Abstract

Multilayered manganese oxide films were prepared on a platinum electrode by potentiostatic oxidation of aqueous Mn2+ ions in the presence of n-tetra-alkylammonium compounds. Alkylammonium cations were intercalated between manganese oxide layers to balance the negative layer charge. Effects of several preparative parameters such as the size of alkylammonium molecules, counteranions, and bath composition on the structure of products were investigated. The interlayer distance of the products increased with increasing alkyl chain length up to C4, and the change became obviously small among C4–C6 compounds. The multilayer formation was achieved only when the manganese concentration was lower than 10 mM, and the highest crystallinity was obtained from a bath composed of 2 mM manganese sulfate and 50 mM alkylammonium chloride. At low concentrations of alkylammonium (<10 mM), a product intercalated with hydrated protons was formed, in which the protons were generated by anodic oxidation of Mn2+ with H2O.

Electrochemical synthesis of birnessite-type layered manganese oxides for rechargeable lithium batteries

“…The previous study [15] indicated that the amount of alkali cations depends on the bath composition and the applied potential. From the X-ray photoelectron spectroscopy, x was estimated to be approximately 0.35 in this study.…”

“…Recently, a new electrochemical method was developed at Yamaguchi University to synthesize birnessite-type layered MnO 2 intercalated with organic molecules such as alkylammonium ions [14,15] and polycations [16]. The electrodeposition process involves a potentiostatic oxidation of aqueous Mn 2+ ions in the presence of a small amount of organic molecules.…”

One-Step Through-Mask Electrodeposition of a Porous Structure Composed of Manganese Oxide Nanosheets

“…Hereafter, this product is abbreviated as Bu-Br in order to distinguish from the Bu 4 NBr reagent. 1, 2, 3, and 4), indicative of a layered structure, as expected for the formation of birnessite-type layered Mn oxide (4)(5)(6)(7)13). With an increase in time of electrolysis, the diffraction peaks increase in intensity without broadening, clearly indicating the growth ECS Transactions, 16 (46) 37-43 (2009) of Mn oxide crystals.…”

Layer-by-layer self-assembly of manganese oxide nanosheets/polyethylenimine multilayer films as electrodes for supercapacitors

“…The separation of the peak energy ( E) is sensitive to the oxidation state of manganese. According to the linear relationship between the average oxidation state of manganese and the E value in the literature [25], the E value (4.86 eV) obtained corresponds to an average oxidation level of 3.7-3.8, which is typical of birnessite-type manganese oxide [26]. In the O 1s region (Fig.…”