Perovskite oxides – a review on a versatile material class for solar-to-fuel conversion processes

Abstract

The thermodynamic and defect chemical opportunities and challenges of perovskite oxides used for thermochemical water and carbon dioxide splitting are reviewed.

Modifying La0.6Sr0.4MnO3 Perovskites with Cr Incorporation for Fast Isothermal CO2‐Splitting Kinetics in Solar‐Driven Thermochemical Cycles

“…Doping beyond x = 0.75 the Cr concentration maintains the rhombohedral structure, however, XRD and Raman analysis of the A g -like mode point to a progressing Jahn-Teller distortion and change in the chromium valence change with a higher Cr 4+ concentration. [8] The lower oxygen release is ascribed to the higher presence of less reducible Cr 4+ cations, in agreement with the XRD and Raman observations. Introducing more Cr dopants on the transition metal ion position of the manganese results in a generally lowered oxygen release.…”

“…In the second step, conventionally operated at a lower temperature, the reduced form of the metal oxide uptakes oxygen from CO 2 and H 2 O injected in the solar reactor, inducing splitting of the reactants by filling the oxygen vacancies of the oxide and producing CO and H 2 , commonly referred to as syngas (Equation (2a,b)). [8]. In addition, the oxide should show favorable thermodynamics toward splitting of CO 2 and H 2 O.…”

“…Perovskites seem promising due to higher capacity for oxygen release than ceria, which eventually leads to higher CO and H 2 yields. [8,25,29] Based on this assumption the total Gibbs free energy of the oxidation of the perovskites La 0.6 Sr 0.4 Cr x Mn 1−x O 3 by splitting CO 2 will have a higher absolute value and higher thermodynamic driving force for CO production with a higher concentration of Cr, i.e., increasing values of x, compared to La 0.6 Sr 0.4 MnO 3 . [10,11] High CO yields were obtained for La 1−x Sr x MnO 3 perovskites (x = 0.4), but the decrease in enthalpy of reduction with increasing Sr content [12] also leads to a lower thermodynamic driving force for fuel production resulting in slower splitting kinetics.…”

Atomic layer deposition of perovskites part 2: Designing next generation electronic applications

“…With perovskites, a wide range of stoichiometries can be achieved, fitting the process requirement for the exchange reactions occurring at the surface. One of the process requirements is that the material remains in the same phase during the reduction and oxidation conditions, where failure would hamper the durability and performance of the system …”

Atomic layer deposition of perovskites—Part 1: Fundamentals of nucleation and growth

“…They may possess ferroelectric, antiferroelectric, dielectric, piezoelectric, pyroelectric, superconductive and magneto‐resistive behavior . These properties have been leveraged for high‐temperature superconductors, high‐efficiency solar cells, high‐k dielectrics for capacitors and transistors, piezoelectric power generators, and as a thermo‐chemical material in the emerging field of solar to energy conversion. With spontaneous and reversible polarization, certain perovskites are ferroelectric in nature .…”