Nanoparticulate Mn0.3Ce0.7O2: a novel electrocatalyst with improved power performance for metal/air batteries

Abstract

In this work, a novel electrocatalyst, Mn 0.3 Ce 0.7 O 2 , with relatively high power performance has been, for the first time, proposed for metal/air batteries. The as-prepared samples are well characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), inductively coupled plasma (ICP) and nitrogen sorption experiments. Meanwhile, electrocatalytic activity towards the reduction of oxygen of Mn 0.3 Ce 0.7 O 2 is compared with those of the pure MnO 2 and CeO 2 . It is observed that the Mn 0.3 Ce 0.7 O 2 solid solution is well formed after the calcination. Electrochemical results show that Mn 0.3 Ce 0.7 O 2 exhibits much higher electrocatalytic activity in the oxygen reduction reaction (ORR) than pure MnO 2 under high discharge current density, which is probably attributed to the effective activation of molecular oxygen over the Mn 0.3 Ce 0.7 O 2 solid solution and higher surface area.

Enhanced photocatalytic activity of nanostructured Fe doped CeO2 for hydrogen production under visible light irradiation

“…It is reasonable to think that the amount of iron in CeO 2 lattice increases up to a certain limit and a higher amount of iron addition does not go into the lattice, causing iron oxide phase as seen in the XRD plot of CF4 and CF5. Addition to this, a small steady decrease in lattice parameter and crystallite size compared to pure ceria is well supported with the broadening of peak and shifting in 2q value to slightly higher degree [35]. This is because of the isomorphous substitution of Ce 3þ or Ce 4þ cations by small size Fe nþ [þ2 / (0.074) and þ3 / (0.064) nm] in the CeO 2 lattice, [38e40] that resulted in lattice contraction and hindrance in crystalline growth of CeO 2 [41,42].…”

“…1 reflects the XRD patterns of the pure CeO 2 and the different weight percent Fe doped CeO 2 nanoparticle. All the diffraction pattern obtained are well indexed to the Face-centered cubic-fluorite structure of CeO 2 (JCPDS 43-1002) [35]. The indexing planes are (111), (200), (220), (311), (222), (400), (331) and (422).…”

“…5(c). The photocatalyst manifest well defined lattice fringes with a d-spacing of 0.31 nm corresponding to the (111) plane of the fluorite structured ceria [35]. However, no lattice fringes related to any FeO x were observed in HRTEM images, which might be assign to the substitution of larger size Ce cations with smaller Fe cations in CeO 2 lattice, thereby the formation of nanosized Fe x Ce 1Àx O solid solutions [35e38].…”

High‐Performance Oxygen Reduction Electrocatalyst Derived from Polydopamine and Cobalt Supported on Carbon Nanotubes for Metal–Air Batteries

“…The electrolyte used in our study was 6 m KOH with 0.01 m Na 2 SnO 3 , 0.5 × 10 −3 m In(OH) 3 , and 7.5 × 10 −3 m ZnO. These additives were introduced so as to inhibit the hydrogen evolution and mitigate Al corrosion, as suggested by a previous study . Primary Al–air batteries were assembled in the same configuration as Zn–air batteries.…”

Porous nanoarchitectures of spinel-type transition metal oxides for electrochemical energy storage systems

“…In the search for more affordable catalytic materials, a number of researchers have devoted their effort to developing metal oxide catalysts with high activity and to utilising them in MABs. [116][117][118][119][120][121][122][123][124][125][126] In particular, spinel-type transition metal oxides have attracted great attention as catalytic materials for MABs due to their relatively low cost and high activity. Spinel-type transition metal oxides based on Co, Mn and/or Ni have been reported to exhibit strong bi-functionality towards the ORR and OER in aqueous alkaline electrolytes: 11,89,127 ORR-OER:…”