In this study, core-shell Fe@Fe2O3 nanowires and multiwall carbon nanotubes (CNTs) were combined with poly(tetrafluoroethylene) (PTFE) and then used as an oxygen-fed gas diffusion electrode. The resulting Fe@Fe2O3/CNT composite electrode was examined by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDX), and transmission electron microscopy (TEM). A novel electro-Fenton (E-Fenton) system was established with the resulting gas diffusion cathode, where hydrogen peroxide was electrogenerated by the reduction of O2 adsorbed on the cathode and iron i...