Fabrication of Mn-Ce Bimetallic Oxides as Electrode Material for Supercapacitors with High Performance

Abstract

Manganese and cerium (Mn-Ce) oxides were prepared under nitrogen and high-temperature oxidation via a bath precipitation method as materials for electrode assemblies in supercapacitors. The prepared Mn-Ce oxide composite was demonstrated to have a high specific capacitance of 163.7 F g À1 with 78.4% cyclic stability after 3000 cycles at a current density of 1 A g À1 . Electrochemical impedance spectroscopy confirms that MnO 2 improves the conductivity of CeO 2 . Results from XPS analysis suggest that the introduction of MnO 2 enhances the concentrations of oxygen vacancies. Finally, band structure, density of states and Mulliken population were calculated using density functional theory, and the findings are consistent with the experimental and characterization results. Because of their excellent performances, Mn-Ce bimetallic oxides are promising electrode materials for supercapacitors.

Ceria-Spiderweb Nanosheets Unlock the Energy-Storage Properties in the “Sleeping” Triplite (Mn2(PO4)F)

“…Based on the established knowledge of the redox chemistries of manganese compounds, − CeO 2 and MnO 2 /CeO 2 , , it is proposed that the well-defined redox couple from the CV curves at E 1/2 ≈ 1.5 V vs Zn/Zn 2+ is related to the sodiation–desodiation process involving the Mn­(II)/Mn­(III) and/or Mn­(III)/Mn­(IV) redox processes (eqs –), while the broad weak redox couple at ca. 1.7 V is related to the Ce­(IV)/Ce­(III) redox process (eq ) as well as the surface adsorption–desorption process (eq ).…”

“…The repetitive GCD, conducted up to 300 cycles, shows that MPF-CeO 2 is more stable than MPF-C-CeO 2 , which perfectly corroborates the scan rate studies (shown in Figure b,g). In general, the high structural stability of MPF-CeO 2 compared to that of the pristine MPF is due to the strong interaction between Mn and Ce because of the higher electrophilic index of Mn (1.55) than that of Ce (1.12), which makes it possible for electrons to be transferred from the Ce to Mn. , …”

“…In general, the high structural stability of MPF-CeO 2 compared to that of the pristine MPF is due to the strong interaction between Mn and Ce because of the higher electrophilic index of Mn (1.55) than that of Ce (1.12), which makes it possible for electrons to be transferred from the Ce to Mn. 38,39 The decreased cycling stability of MPF-C-CeO 2 compared to that of MPF-CeO 2 could be attributed to the differences in the morphologies of these two samples; micron-sized aggregated nanoparticles (MPF-CeO 2 ) vs high-surface-area nanoporous material (MPF-C-CeO 2 ). It is well known that micron-sized cathode materials provide better electrochemistry for battery and batterylike systems than the nanosized cathode materials.…”

Rare Earth‐Based Nanomaterials for Supercapacitors: Preparation, Structure Engineering and Application

“…The chemical precipitation has been successfully applied to the synthesis of a variety of RE compounds and their hybrids, such as Ce-based materials, [32][33][34][35] La 2 O 3 , [36] Y 2 O 3 , [37] and so on. For instance, Arul et al synthesized CeO 2 /Fe 2 O 3 composite nanospindles by chemical co-precipitation method.…”