Morphologically Tuned Lead‐Free Perovskite ZnSnO ₃ for Dye‐Selective Photocatalytic Degradation

ABSTRACT Morphology‐tuned lead‐free perovskite ZnSnO 3 was synthesized via dual‐hydrolysis‐assisted liquid precipitation method along with hydrothermal treatment followed by calcination. The rhombohedral 3D cuboids were transformed to orthorhombic 2D flake‐like structures due to an increase in the duration of hydrothermal treatment. The photodegradation ability of the samples was explored by employing two dyes with different ionic identities. The degradation performance was found to be influenced by the crystal structure, surface charge (conveyed by the zeta potential), and effective surface area of the catalysts. The nanoflake ZnSnO 3 , possessing the highest negative zeta potential of −23.8 mV, showed a maximum rate constant of 0.07495 min −1 to remove the cationic dye rhodamine B (RhB). Conversely, the cube‐like ZnSnO 3 , with the lowest negative zeta potential of −5.3 mV, disintegrated the anionic dye methyl orange (MO) with a maximum rate constant of 0.02649 min −1 . Active radicals •O 2 − , •OH, and h + were attributed for the degradation of RhB. Along with the reusability test, catalyst load variation and pH of active medium variation for RhB, the degradation performances for different dye mixtures (RhB + MO), other dyes (methylene blue [MB], eosin B [EB]), and an invisible harmful water‐soluble chemical (phenol), suggest ZnSnO 3 as a potential candidate for a future water‐cleaning dye degradation agent.