Superior "Adsorption Pump" Functionality of Pr(OH)₃ Catalysts Enables Efficient Antibiotic Degradation via...

Rare-earth-based catalysts show promising potential for degrading emerging pollutants in advanced oxidation processes (AOPs). In this work, a porous Pr(OH)₃ catalyst (denoted as PrH) was successfully synthesized via an alkali-induced self-templating strategy, using an f-d cyanide-bridged coordination framework as the precursor. The unique porous architecture of PrH, combined with its abundant surface hydroxyl groups, synergistically functions as a powerful "adsorption pump", efficiently enriching antibiotic norfloxacin (NOR) on the catalyst surface through ligand exchange. Subsequently, the concentrated pollutants are degraded via PMS activation, driven by the reversible Pr^{3 +}/Pr^{4 +} redox cycle at the Pr sites. This intrinsic adsorption-catalysis synergy, centered on the bifunctional Pr centers, effectively enhances the local concentration of reactants and promotes the utilization of reactive oxygen species, leading to high degradation efficiency even at low catalyst dosages. Furthermore, the PrH catalyst exhibits good cycling stability, maintaining high structural integrity over repeated use. This work not only provides an efficient strategy for designing porous rare-earth catalysts but also offers valuable insights into the synergistic adsorption-catalysis mechanism for antibiotic removal.