Novel catalytic properties of quadruple perovskites

Abstract

Quadruple perovskite oxides AA'₃B₄O₁₂ demonstrate a rich variety of structural and electronic properties. A large number of constituent elements for A/A'/B-site cations can be introduced using the ultra-high-pressure synthesis method. Development of novel functional materials consisting of earth-abundant elements plays a crucial role in current materials science. In this paper, functional properties, especially oxygen reaction catalysis, for quadruple perovskite oxides CaCu₃Fe₄O₁₂ and AMn₇O₁₂ (A = Ca, La) composed of earth-abundant elements are reviewed.

Keywords: 107 Glass and ceramic materials; 205 Catalyst / photocatalyst / photosynthesis; 206 Energy conversion / transport / storage / recovery; 207 Fuel cells / batteries / super capacitators; 50 Energy Materials; 504 X-ray / Neutron diffraction and scattering; Quadruple perovskite; catalysis; high-pressure synthesis.

Graphical abstract

Figure 1.

Crystal structure of simple (ABO₃-type) and quadruple (AA′₃ B ₄O₁₂-type) perovskites.

Figure 2.

Temperature dependence of the unit cell volume (a) and differential scanning calorimetry curves (b) of LaCu₃Fe_4–xMn_xO₁₂ (x = 0, 0.5, 0.75, 1, and 1.5). Reproduced from [53] with permission from AIP Publishing LLC.

Figure 3.

Temperature dependence of the cubic a-axis length for SrCu₃Fe_4–xMn_xO₁₂ (x = 0, 0.5, 1, 1.25, 1.5, and 1.75). Reprinted from [54] with permission from AIP Publishing LLC.

Figure 4.

Linear sweep voltammograms in OER conditions for perovskite oxide and RuO₂ catalysts. Reproduced from [55].

Figure 5.

(Top) OH⁻ adsorbates on FeO₂-terminated (100) planes of CaCu₃Fe₄O₁₂. The interatomic distance between the nearest neighboring OH adsorbates is ∼2.6 A. (Bottom) Proposed OER reaction mechanism for CaCu₃Fe₄O₁₂. Reproduced from [55].

Figure 6.

Cyclic voltammograms of SrFeO₃, CaFeO₃, and CaCu₃Fe₄O₁₂ for 100 sequential OER measurements. Reproduced from [55].

Figure 7.

(Left) Crystal structures and (right) electron density maps of SrFeO₃ (equal-density level: 0.4 Å⁻³) and CaCu₃Fe₄O₁₂ (equal-density level: 0.5 Å⁻³). Reproduced from [55].

Figure 8.

Linear sweep voltammograms in OER conditions for AMnO₃, AMn₇O₁₂ (A = Ca, La), and RuO₂. The inset illustrates the enlarged data in the vicinity of the current density onset. Reproduced from [65] with permission from John Wiley & Sons.

Figure 9.

The specific activities versus average Mn–Mn intermetallic distances calculated for edge-shared MnO₆ octahedra (Mn₂O₃, Mn₃O₄), corner-shared MnO₄ pseudosquare plane–MnO₆ octahedron (CaMn₇O₁₂, LaMn₇O₁₂), and corner-shared MnO₆ octahedra (CaMnO₃, LaMnO₃). Reproduced from [65] with permission from John Wiley & Sons.

Figure 10.

Proposed OER mechanism for LaMn₇O₁₂ via direct O–O bond formation between the unsaturated MnO₄ plane (green, right triangle) and the unsaturated MnO₆ octahedron (orange, left triangle). Reproduced from [65] with permission from John Wiley & Sons.

Figure 11.

Catalytic activity of manganese perovskites obtained by using a rotating ring/disk electrode equipment. Disk/ring current densities are plotted as a function of applied disk potential in ORR conditions for AMnO₃, AMn₇O₁₂ (A = Ca, La), and reference catalysts (acetlylene black (AB), Platinum-carbon composite (Pt/C)). Reproduced from [65] with permission from John Wiley & Sons.