Abstract: Electrocatalytic particle electrodes (i.e., MO_x/AC), including TiO₂/AC, MnO₂/AC, SnO₂-Sb/AC and SnO₂-Sb-Mn/AC, were prepared using sol-gel, redox and thermal decomposition methods. Their physical composition, micro morphology as well as electrocatalytic activity were investigated with X-ray diffraction (XRD), scanning electron microscope (SEM) and cyclic voltammetry (CV). The results indicated that Ti, Mn, Sn-Sb and Sn-Sb-Mn oxides were crystallized into different microstructures on the surface of the activated carbon (AC). The lattice sizes for TiO₂, MnO₂, SnO₂-Sb and SnO₂-Sb-Mn particles were 10.64,1.34,4.68 and 13.50 nm, respectively. Besides, the electrocatalytic activity of the virgin AC was improved with the presence of these nano semiconductor metal oxides. The electrocatalytic activities of the prepared MO_x/AC particle electrodes followed the order:SnO₂-Sb-Mn/AC>TiO₂/AC>SnO₂-Sb/AC>MnO₂/AC. Electrochemical oxidation of simulated phenolic wastewater was conducted to investigate phenol degradation properties with a MO_x/AC particle electrode system. The experimental results illustrated that a higher phenol and COD_Cr removal efficiency could be achieved after the implantation of the active components. The phenol and COD_Cr removal efficiencies with TiO₂/AC, MnO₂/AC, SnO₂-Sb/AC and SnO₂-Sb-Mn/AC particle electrode systems at current density 8.0 mA/cm² with electrolysis time 2.72 h were 87.1% and 92.5%, 92.8% and 89.3%, 90.4% and 88.7%, and 100% and 97.2%, respectively, higher than those of AC, which were 84.2% and 79.1%. Furthermore, compared to virgin AC particle, MO_x/AC displayed a feature of no accumulation of benzoquinone, and is therefore considered to be a more environmentally compatible material. Our study confirmed the superior electrocatalytic performance of MO_x/AC as compared to virgin AC.