Synthesis, Characterization, and Photocatalytic Performance of Mesoporous α-Mn₂O₃ Microspheres Prepared via a Precipitation Route

Abstract

-Mn 2 O 3 microspheres with high phase purity, crystallinity, and surface area were synthesized by the thermal decomposition of precipitated MnCO 3 microspheres without the use of any structure directing agents and tedious reaction conditions. The prepared Mn 2 O 3 microspheres were characterized by Fourier transform infrared (FTIR) spectroscopy, powder X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), transmission electron microscopy (TEM), and Brunauer-Emmett-Teller (BET) and photoluminescence (PL) studies. The complete thermal transformation of MnCO 3 to Mn 2 O 3 was clearly shown by the FTIR and XRD analysis. The electron microscopic images clearly confirmed the microsphere-like morphology of the products with some structural deformation for the calcined Mn 2 O 3 sample. The mesoporous texture generated from the interaggregation of subnanoparticles in the microstructures is visibly evident from the TEM and BET studies. Moreover, the Mn 2 O 3 microstructures showed a moderate photocatalytic activity for the degradation of methylene blue dye pollutant under UV light irradiation, using air as the potential oxidizing agent.

Gate Interface Engineering for Subvolt Metal Oxide Transistor Fabrication by Using Ion-Conducting Dielectric with Mn2O3 Gate Interface

“…Annealing at 550 °C for 30 min shows thermochemical changes of the peak positions. However, the GIXRD study shows (Figure b) only the two most intense peaks that are indexed as the crystal planes of (222) and (440) of Mn 2 O 3 . , Moreover, GIXRD was performed (not shown here) to check the crystallographic phase of the dielectric Li incorporated alumina. However, we did not find any crystalline phase, concluding mostly the amorphous nature of the dielectric.…”

Visible-Light Photocatalytic Water Splitting and Norfloxacin Degradation by Reduced Graphene Oxide-Coupled MnON Nanospheres

“…400), (332), ( 431), ( 440), ( 622), (631), and (444), characteristic of MnON with a lattice parameter a = 0.9409 nm (JCPDS: 00-041-1442). 28,29 The XRD patterns of MnON/ RGO composites show all the peaks corresponding to MnON, in addition to the peaks of RGO at 10.3°marked with "*" symbol. 30 The pristine nature of the synthesized material is indicated by the lack of any impurity peaks corresponding to other phases.…”

“…The average particle size was determined as approximately 45 nm, as shown in Figure g, h. Figure a shows the XRD patterns of the MnON and MnON/RGO­(1:1, 1:2, and 1:3). The diffraction peaks at 2θ = 23.2°, 32.8°, 35.5°, 38.4°, 45.1°, 49.4°, 56.7°, 64.2°, and 66.7° correspond to the (211), (113), (222), (400), (332), (431), (440), (622), (631), and (444), characteristic of MnON with a lattice parameter a = 0.9409 nm (JCPDS: 00-041-1442). , The XRD patterns of MnON/RGO composites show all the peaks corresponding to MnON, in addition to the peaks of RGO at 10.3° marked with “*” symbol . The pristine nature of the synthesized material is indicated by the lack of any impurity peaks corresponding to other phases.…”