One-step combustion synthesis of C-Mn₃O₄/MnO composites with high electrochemical performance for supercapacitor

Temperature‐dependent synthesis of Mn 3 O 4 nanostructures by microwave irradiation method for high‐performance supercapacitors

“…The core‐level O 1s spectrum of the Mn‐150 sample is shown in Figure 5C and was fitted to three peaks. The fitting peak observed at 529.5 eV is corresponds to the Mn‐O‐Mn bond, while the other two peaks centered at 531.3 (Mn‐O‐H) and 532.6 eV (H‐O‐H) 16,34 …”

“…The fitting peak observed at 529.5 eV is corresponds to the Mn-O-Mn bond, while the other two peaks centered at 531.3 (Mn-O-H) and 532.6 eV (H-O-H). 16,34…”

“…7,8 Different synthesis methods and chemical compositions may affect the catalyst morphology and structure, which may change the catalytic activity. 9 Mn 3 O 4 nanoparticles have been synthesized by various methods, including polyetherimide-templated (spherical, 8.7-31.5 nm), 10 chemical precipitation (spherical, ~20 to 50 nm), 11 ultrasound-assisted ball milling (small size, ~30 nm), 12 hydrothermal (nanorods, 5-30 nm), 13 solvothermal (irregular, 12-40 nm), 14 sol-gel (spherical, 1 μm), 15 combustion (spherical, ~43 nm), 16 low temperature (spherical, 35 nm), 17 and microwave combustion (spongy aggregates, 28.08 nm) synthesis methods. 18 Among these, microwave-assisted synthesis methods have certain advantages, including simple procedure, rapid and selective heating, energy-saving, higher yields, high purity, small and narrow particle size distribution, lower processing cost, and eco-friendliness.…”

Influential Role of Elemental Migration in a Composite Iron–Zeolite Catalyst for the Synthesis of Aromatics from Syngas

“…For the NFM catalyst before the reaction, the Fe phases were identified as Fe 3 O 4 and Fe 2 O 3 located at 709.3 and 710.4 eV (Figure 4a), 48−51 while the Mn phases consisted of Mn 3 O 4 , Mn 2 O 3 , and MnO 2 at 640.8, 641.5, and 642.4 eV, respectively (Figure 4b). 52,53 After the reaction, Fe 3 O 4 and Fe 2 O 3 were still observed in the Fe 2p pattern (Figure 4d), partly due to the oxidation of NFM after unloading the catalyst, while an extra peak of iron carbide at 708.6 eV was generated during the reaction. 54 Meanwhile, the Mn 2 O 3 and MnO 2 in Mn phases were reduced to form the MnO and Mn 3 O 4 phases, 55 as exhibited in Figure 4e.…”

“…The peaks at 710.0 and 641.8 eV were identified as Fe−Al and Mn−Al bonds, respectively, indicating that part of the migrated elements of Fe and Mn has bonded with the zeolite framework. 48,52,76,77 Na was also observed on the zeolite, as shown in Figure S24; the peak at 1071.8 eV was identified as the Na + ion; hence, it was speculated that Na was electrostatically adsorbed on the framework of the zeolite.…”