Non-radical oxidation triggered by hollow MOFs-derived carbon in persulfate-based AOPs are potential for antibiotic wastewater remediation. However, the inherent relationship between hollow structure and catalytic activity and mechanism evolution involving the transformation from solid structure to hollow framework was not clear enough. Given this, hollow ZIF-8-derived carbon (HZC) was fabricated via TA etching and carbonization for PDS activation. The results indicated that HZC-800 possessed excellent antibiotic removal performance through electron-transfer mediated non-radical oxidation. Characterizations revealed the key role of graphitic N in the catalytic reaction that was linearly correlated with kinetic constant (k), and higher graphitic N enhanced antibiotic degradation. Further analysis suggested that mechanism evolution from ROS-dominated process in solid ZIF-8-derived carbon (ZC-800)/PDS to electron-transfer oxidation in HZC-800/PDS stemmed from hollow structure transformation. Compared with solid ZC-800, hollow HZC-800 with higher graphitic N and lower electron-withdrawing O groups enhanced electron conductivity and was more conducive to PDS adsorption and forming activated PDS* for electron-transfer non-radical oxidation, reducing directly activating PDS into ROS. HZC-800 with larger porosity and more defects facilitated mass diffusion for antibiotic removal with great practicality. This study provided a new insight into mechanism transformation from hollow structure evolution and designing carbon catalysts for wastewater treatment.

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