Synthesis of Alumina-Grafted Manganese Oxide Particles Using Surfactants through Coprecipitation Method and Their Thermal Properties

Abstract

Alumina particles were grafted onto the surface of manganese oxide particles via the coprecipitation process using surfactant and cosurfactant. The phase of Mn/Al salts (Phase I) and the phase of precipitation agent (Phase II) were prepared in aqueous surfactant solution, separately. Phase II was added into Phase I and the reaction was performed to form the precursors of composites through hydrogen bonding between Mn(OH) 2 and Al(OH) 3 prepared by the reaction of Mn/Al salts with the precipitation agent. The alumina-grafted manganese oxide particles were obtained as a final product after calcination. The concentrations of Al salt and surfactant were varied to investigate their effects on the formation and the crystallinity of composites. In addition, the crystal structure of products could be controlled by changing the calcination temperature. Through thermal analyses, it was found that the thermal stability of manganese oxide was improved by the introduction of alumina on its surface.

In-Situ H2O2 Cleaning for Fouling Control of Manganese-Doped Ceramic Membrane through Confined Catalytic Oxidation Inside Membrane

“…The average pore sizes of the pristine and Mn-doped membrane active layers were 780 nm (Figure S1a) and 792 nm (Figure S1b), respectively. As shown in Figure 3, the Mn 2p3/2 spectrum showed two distinct peaks at 641.6 eV and 643.2 eV in the Mn-doped membrane layer, which were consistent with the binding energy of Mn(III) and Mn(IV) [25][26][27]. This demonstrated that the doped manganese in the Mn-doped membrane existed as two oxidation states (Mn 3+ and Mn 4+ ).…”