Crystal chemistry of hexaaluminates: β-alumina and magnetoplumbite structures

Reverse Water Gas Shift by Chemical Looping with Iron-Substituted Hexaaluminate Catalysts

The Fe-substituted Ba-hexaaluminates (BaFeHAl) are active catalysts for reverse water-gas shift (RWGS) reaction conducted in chemical looping mode. Increasing of the degree of substitution of Al3+ for Fe3+ ions in co-precipitated BaHAl from 60% (BaFeHAl) to 100% (BaFe-hexaferrite, BaFeHF), growing its surface area from 5 to 30 m2/g, and promotion with potassium increased the CO capacity in isothermal RWGS-CL runs at 350–450 °C, where the hexaaluminate/hexaferrite structure is stable. Increasing H2-reduction temperature converts BaFeHAl to a thermally stable BaFeHF modification that contains additional Ba-O-Fe bridges in its structure, reinforcing the connection between alternatively stacked spinel blocks. This material displayed the highest CO capacity of 400 µmol/g at isothermal RWGS-CL run conducted at 550 °C due to increased concentration of oxygen vacancies reflected by greater surface Fe2+/Fe3+ ratio detected by XPS. The results demonstrate direct connection between CO capacity measured in RWGS-CL experiments and calculated CO2 conversion.

Retracted Article: Novel Rh-substituted hexaaluminate catalysts for N2O decomposition

Novel Rh-substituted hexaaluminate catalysts were prepared for the first time for N₂O decomposition as a green propellant.

Hexaaluminates: a review of the structure, synthesis and catalytic performance

The structure and catalytic applications of hexaaluminates.

Effect of magnesium substitution into Fe-based La-hexaaluminates on the activity for CH4 catalytic combustion

The introduction of Mg²⁺ into Fe-based La-hexaaluminates significantly enhanced the activity for CH₄ catalytic combustion and the resistance to deactivation after calcination at 1300 °C.

A novel Ir-hexaaluminate catalyst for N(2)O as a propellant

Aiming for designing a novel catalyst for N(2)O as a green propellant, Ir-substituted hexaaluminate, which can initiate N(2)O decomposition at 623 K and can sustain the stability at 1473 K, has been developed for the first time.