Construction of hierarchically porous ZnO@ZIF-8 for enrichment and sensitive detection of bisphenols in environmental matrices.

Due to their environmental durability and potential for bioaccumulation, bisphenol compounds result in serious threats to biological systems and human well-being, necessitating the development of extremely effective analytical techniques for trace-level monitoring. In this work, a sacrificial-template strategy was employed, in which ZnO served as both the structural scaffold and precursor to direct the controlled growth of ZIF-8, resulting in a hierarchical micro-mesoporous ZnO@ZIF-8 composite. This architecture effectively mitigated the mass-transfer limitations commonly associated with conventional microporous metal-organic framework materials. When employed as a dispersive solid-phase extraction adsorbent, the composite reached adsorption equilibrium rapidly within 3 min, offered ultralow detection limits (0.03-0.1 ng mL-1), and showed high adsorption capacities of 381-408 mg g⁻¹. These characteristics confirm its strong potential for the highly sensitive analysis of bisphenol pollutants in intricate environmental matrices.