It is important to develop novel electrocatalytic membranes for efficiently remove micropollutants from water and wastewater. In this study, two CeO₂ samples (denoted as CeO₂-N and CeO₂-O, respectively) were synthesized to modify the carbon nanotube (CNT)-based membrane. CeO₂-N exhibited a higher proportion of O_ad and O_lat to the formation of O_v. In contrast, CeO₂-O possessed a cubic cerianite structure with less O_v. As a result, the CeO₂-N@CNT-based membrane displayed a smaller equivalent polarization resistance of 5.6 Ω/cm² and lower potential differences of 0.19 V compared to the CeO₂-O@CNT-based membrane, which had an equivalent polarization resistance of 6.9 Ω/cm² and potential differences of 0.51V. Consequently, the CeO₂-N@CNT-based membrane demonstrated superior performance in diclofenac (DCF) removal compared to the CeO₂-O@CNT-based membrane. Due to its planes with lower apparent activation energy and higher single electron transfer rate, the CeO₂-N@CNT-based membrane generated a greater amount of ¹O₂. Conversely, the CeO₂-O@CNT-based membrane generated more ·OH. Therefore, DCF mainly underwent degradation via C-N bond cleavage and decarboxylation through direct attack of ¹O₂ for the CeO₂-N@CNT-based membrane, while ·OH played a significant role in removing DCF via hydrogen loss, chlorine loss and C-N cleavage for the CeO₂-O@CNT-based membrane.