Predicting Trends in the Bond Structure and Electronic Properties of Mixed-Transition-Metal Strontium Oxide Perovskites

Solar radiation, the most abundant energy resource on Earth, can be converted to electricity using photovoltaic panels. For electrons to reach the absorber material, the top electrode of the device must be a transparent conductor (TC). The state-of-the-art material for this purpose is indium tin oxide. The availability of indium, a metal found in various ores at concentrations under 0.01%, limits the adoption of this technology, and has motivated the search for alternative TC. Cubic Sr-based perovskites SrMO₃(M =V,Nb,Mo,W) show promise as technologically scalable TC if they can be stabilized against the formation of charge-compensating Sr vacancies [1,2]. Including multiple B cations may enable the Entropy stabilization [3] of this structure. To understand the effect of the coexistence of cations on the band structure and establish design rules for high entropy perovskites, the electronic properties of SrB_1-xB’_xO₃ (B, B’={Ti,V,Cr,Nb,Mo,Ta,W} and x={0.25, 0.5, 0.75}) have been predicted from DFT+U calculations [4]. Four magnetic orderings of these systems were studied: the ferromagnetic, the antiferromagnetic phases with alternating planes of aligned spins in the [001], [110], and [111] directions. The effect of Sr deficiencies on the electronic properties are also investigated.