LaMnO 3 Dopants for Efficient Thermochemical Water Splitting Identified by Density Functional Theory Calculations

Wang, Ximeng; Goyal, Anuj; Zhou, Peng; Gager, Elizabeth; McCord, Dylan; Nino, Juan C.; Scheffe, Jonathan R.; Lany, Stephan; Phillpot, Simon R.

doi:10.1021/acs.jpcc.3c06835

DOE OSTI · 2274782

LaMnO 3 Dopants for Efficient Thermochemical Water Splitting Identified by Density Functional Theory Calculations

Wang, Ximeng·Goyal, Anuj·Zhou, Peng·Gager, Elizabeth·McCord, Dylan·Nino, Juan C.·Scheffe, Jonathan R.·Lany, Stephan·Phillpot, Simon R.

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Abstract

While ceria is the standard material for two-step water splitting, perovskites are emerging as viable alternatives. In this work, based on the orthorhombic LaMnO 3 supercell, we substitute Li Na K Rb Mg Ca Sr Ba on the A-sites (La sites) and Al Ga In Mg Zn on the B-sites (Mn sites) at a concentration of 37.5%. The range of temperature and oxygen partial pressure at which each composition is stable is predicted. For compositions that are stable in relevant temperature and pressure ranges, the oxygen vacancy formation energies are determined for all of the oxygen vacancy site positions available in the computational supercell. Mg, Ca, Sr, and Ba A-site-substituted LaMnO 3 and Al and In B-site-substituted LaMnO 3 meet these two criteria for candidates in solar-thermal water splitting applications. Finally, oxygen vacancy formation energy can also be controlled by adjusting the doping strategy.

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08 HYDROGEN 14 SOLAR ENERGY 37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY chemical structure defects in solids density functional theory energy hydrogen oxygen transition metals

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Wang, Ximeng, Goyal, Anuj, Zhou, Peng, Gager, Elizabeth, McCord, Dylan, Nino, Juan C., Scheffe, Jonathan R., Lany, Stephan, Phillpot, Simon R.. 2023-12-05. LaMnO 3 Dopants for Efficient Thermochemical Water Splitting Identified by Density Functional Theory Calculations. https://doi.org/10.1021/acs.jpcc.3c06835

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