Ingeniously combines phase transfer process and triazole MOF expansive action to prepare porous carbon beads for ozone oxidation: Preparation process and synergistic mechanism

The removal of persistent organic pollutants through catalytic ozonation remains a significant challenge, particularly in developing catalysts that combine high efficiency with robust stability. To address this, we present an innovative strategy for synthesizing a series of energetic metal-organic framework (EMOF)-derived porous carbon spheres doped with various transition metals (denoted as EMS, EMFeS, EMCuS, EMNiS, and EMMnS). This approach combines a phase transfer pathway with controlled expansion of energy-containing MOFs during high-temperature pyrolysis, resulting in hierarchically porous structures. When applied to tetracycline (TTCH) degradation, EMFeS exhibited remarkable catalytic activity with ozone and the reaction rate constant is 0.131 min⁻¹, which is superior to individual ozone system (0.088 min⁻¹). The superior catalytic performance is attributed to two aspects: (i) The three-dimensional hierarchical porous architecture facilitates efficient mass transfer and improves reaction kinetics, while (ii) the well-dispersed metal active sites (including Mn, Fe, Cu, and Ni) significantly enhance ozonolysis efficiency. Comprehensive mechanistic studies through quenching experiments and LC-MS analysis elucidated the degradation pathways, while continuous flow catalytic tests and biotoxicity assessments confirmed the practical applicability of these catalysts. This work not only advances the development of high-performance ozonation catalysts but also provides new insights into the design of water treatment materials.