Pd/UiO‐66(Zr)‐2OH as a High‐Performance Catalyst for Hydrogen‐Enhanced Fenton Oxidation of Trimethoprim

Abstract

A novel catalyst material named Pd/UiO‐66(Zr)‐2OH was successfully developed and applied in a hydrogen‐promoted Fenton system for the efficient catalytic oxidation of the widely used antibiotic trimethoprim (TMP). The UiO‐66(Zr)‐2OH, as the carrier of catalyst in this work, was synthesized through a solvothermal method. The Pd0 nanoparticle, as the active center of the catalyst, was loaded onto its surface by the “ship‐in‐a‐bottle” strategy. The results showed that the composite Pd/UiO‐66(Zr)‐2OH demonstrated excellent catalytic performance during the reaction, achieving over 97% of TMP removal efficiency within 180 min under optimal conditions under the condition of only trace of iron without adding H2O2. This may be attributed to the fact that the [H], as a clean and efficient reducing agent, can be utilized to accelerate the regeneration of Fe2+ in the Fenton reaction, as well as in the in‐situ regeneration of H2O2. The key parameters affecting the removal efficiency of TMP, including the initial pH and concentration of Fe2+, the dosage of the synthesized material, the flow rate of H2 and the stirring speed were investigated systematically. The Pd/UiO‐66(Zr)‐2OH exhibited high stability and reusability, maintaining over 82% of its initial degradation efficiency of TMP after six reaction cycles. The mechanistic insight revealed that the system primarily relied on the generation of hydroxyl radical (·OH) and singlet oxygen (1O2) for the degradation of TMP, which was verified through quenching experiments and electron spin resonance (ESR). The degradation pathway of TMP was elucidated by analyzing intermediates and the reduction in total organic carbon (TOC). This research offers novel conceptual insights into the evolution and application of advanced oxidation technologies, efficient degradation of emerging pollutants, and expansion of pathways for hydrogen resource utilization.