Synthesis of Pd/CeOx/Nano-graphite composite cathode for electro-catalytic degradation of phenol

To improve the cathode electro-catalytic degradation performance of electrochemical advanced oxidation processes (EAOP), Pd metal and CeO x co-modified Nano-graphite (Pd/CeO x /Nano-G) composite was synthesized by chemical precipitation and reduction methods, and Pd/CeO x /Nano-G cathode was prepared by a hot-pressing method. The as-prepared composite and electrode were characterized by X-ray photoelectron spectroscopy, X-ray diffraction and scanning electrons microscopy. Results revealed that the mix-crystal structural CeO x (Ce 2 O 3 and CeO 2 ) and Pd 0 metal were formed. The cathode was applied for the electro-catalytic degradation of phenol wastewater. The degradation efficiency of phenol by Pd 1.0 /CeO x5.0 /Nano-G cathode reached 99.6% within 120 min degradation, which were higher than that of CeO x5.0 /Nano-G and Nano-G cathodes. Both of the Pd metal and CeO x could improve the O 2 reduction to H 2 O 2 and promote the H 2 O 2 dissociation to •OH for phenol oxidation. Additionally, the effects of electro-catalytic reaction parameters on the phenol degradation were investigated. The results indicated that Pd/CeO x /Nano-G cathode would have promise for further practical application in organic wastewater treatment.