ABSTRACT Water contamination by persistent pharmaceuticals and herbicides poses a serious environmental challenge for the development of efficient and sustainable photocatalysts. In this regard, ZIF‐8 (Z8) was thermally transformed into calcined ZIF‐8 (CZ8), a porous ZnO‐based photocatalyst exhibiting a reduced band gap, enhanced charge separation, and improved reusability. The photocatalytic activity of CZ8 was evaluated for the degradation of ciprofloxacin (CIP) and atrazine (ATZ) under natural sunlight irradiation covering the UV visible range. Compared to pristine Z8, CZ8 demonstrated significantly enhanced photocatalytic performance due to improved light harvesting and suppressed charge recombination. CZ8 achieved ∼94% CIP removal within 120 min, following pseudo‐first‐order kinetics with an apparent rate constant of 0.019 min − 1 , which is more than twice that of Z8 (0.0086 min − 1 ). Similarly, CZ8 exhibited superior ATZ degradation efficiency within 180 min. Optimal performance was observed at neutral pH, while sustained activity under acidic and basic conditions highlights the robustness of CZ8 for practical wastewater treatment. These results demonstrate that thermal transformation of ZIF‐8 into CZ8 is an effective strategy for developing sunlight‐driven photocatalysts for environmental remediation.
Das et al. (2026) studied this question.