High-entropy single-phase oxides with the perovskite structure Ca(TiSnNbTaM)O (M = Fe, Zr) were synthesized for the first time by a simple one-step ceramic method and characterized by X-ray diffraction analysis. The powders were subjected to mechanical activation, which resulted in a partial phase transition from an orthorhombic phase to a tetragonal one. Both compositions demonstrated the ability to reduce Cr(VI) when illuminated with uV light and high sorption activity with respect to the methylene blue dye.
Estemirova et al. (Wed,) studied this question.