Pressure-Regulated Enzyme-Equivalent Strontium Cobalt Oxide "Perovzymes" with Phase-Dependent Activity

Enzymes exhibit remarkable structural adaptability, often exhibiting structure-dependent catalytic performance. Despite the emergence of perovskite-based inorganic oxides as promising enzyme-like catalysts, the effect of crystal structure modulation on their catalytic activity remains unknown. In this context, we demonstrate the SrCoO3-δ (δ = 0.3-0.5) perovskite system as an enzyme mimic that possesses a rich phase landscape spanning hexagonal to cubic structures. Herein, we investigated the effect of pressure-controlled phase transformations between the oxygen-deficient orthorhombic phase (SCO-1) and oxygen-rich tetragonal phase (SCO-16) of SrCoO3-δ on enzyme-like activity. The oxidase enzyme-like activity showed a distinct dependence on the crystal structure transition from orthorhombic to tetragonal, resulting in nearly fivefold higher activity in the tetragonal phase compared to its orthorhombic counterpart. Owing to the excellent scalability, heterogeneous nature, and superior operational stability, we utilized our system in phenolic pollutant detection. Notably, compared to natural laccase enzyme, which typically suffers from poor durability, limited tolerance to harsh conditions, and limited recyclability, SCO-16 exhibits sustained catalytic efficiency, enhanced robustness, and excellent reusability over multiple cycles, making it suitable for environmental remediation. In all, the distinct phase-dependent enzyme-like activity of pressure-regulated perovskite phases establishes a new direction in enzyme-like materials design.