A very simple method to synthesize nano-sized manganese oxide: an efficient catalyst for water oxidation and epoxidation of olefins

Abstract

Nano-sized particles of manganese oxides have been prepared by a very simple and cheap process using a decomposing aqueous solution of manganese nitrate at 100 °C. Scanning electron microscopy, transmission electron microscopy and X-ray diffraction spectrometry have been used to characterize the phase and the morphology of the manganese oxide. The nano-sized manganese oxide shows efficient catalytic activity toward water oxidation and the epoxidation of olefins in the presence of cerium(IV) ammonium nitrate and hydrogen peroxide, respectively.

Nano-sized manganese oxides as biomimetic catalysts for water oxidation in artificial photosynthesis: a review

“…The oxygen evolution rate increases with increasing concentration of Ce(IV). The increase in the oxygen evolution rate in low concentration of Ce(IV) is fast in the Ce(IV) concentration range of 0.01 -0.1 M. However, in higher concentrations of Ce(IV), the slope of the increasing the oxygen evolution rate is slow (is less steep) [65].…”

“…The nano-sized manganese (III) oxide also showed a high activity in epoxidation of aromatic olefins and a mild activity in the epoxidation of some non-aromatic olefins in the presence of H 2 O 2 and bicarbonate ion [65].…”

“…The X-ray diffraction (XRD) pattern of as-prepared manganese oxide showed that the compound is a-Mn 2 O 3 . SEM images determined that the compound consists of particles of less than 100 nm in size (figure 4) [65]. Transmission electron microscopy (TEM) images allowed us to determine that the compound consists of both amorphous and crystalline phase.…”

“…Nano-sized manganese oxides are known to be useful, versatile and environmentally friendly catalysts for important reactions, and there are many methods for the synthesis of these compounds [65][66][67][68]. Among them, solvothermal, polymeric-precursor and surfactantmediated routes are quite popular.…”

Facile Synthesis of Graphene-supported MnO, Mn3O4, and MnO2Nanocomposites by Controlling Gas Environment

“…MnO x nanocomposites have attracted increasing attention in photocatalysis, energy storage, and Li ion batteries because of their low cost, environmental abundance, and high theoretical specific capacitances. 4,5 Recently, several research groups have reported that graphene-supported MnO x nanocomposites can play a critical role in energy storage [5][6][7] and can be prepared by using an aqueous chemical method, 8 chemical reduction, [9][10][11] and colloidal mixing. 12 However, these methods are somewhat complicated and require different synthetic protocols to prepare specific MnO x nanoparticles (NPs) on graphene, which makes it difficult to produce those nanocomposites.…”