Preparation of ferric oxide for efficient electrocatalytic oxidation of methylene blue

Abstract

Ferric oxide has been prepared by a co-precipitation method, which can be served as a kind of electrode material for electrocatalytic oxidation of methylene blue (MB). The as-prepared ferric oxide displays a regular cubic structure, which can provide a large specific surface area to facilitate the transfer of electrolyte ions. MB solution has been used as the simulated wastewater for electrocatalytic degradation experiments to investigate the electrocatalytic activities of ferric oxide electrode. The electrochemical performance of ferric oxide electrode and the electrocatalytic oxidation efficiency of MB have been tested. It has been found that ferric oxide electrode possesses excellent electrocatalytic performance in the degradation of MB. The ferric oxide electrode shows a high degradation efficiency up to 95.56% in 90 min. NaCl solution is selected as the optimum electrolyte because Cl− in the NaCl solution can lose electrons to form active chlorine. The active chlorine can be further hydrolyzed into HClO, which can greatly enhance the degradation efficiency of MB. The q*T and q*O are nearly consistent in different electrolyte and the values are calculated to be 1.60 and 0.03, respectively. Additionally, after 5 cycle tests, the ferric oxide electrode still shows enough electrocatalytic activity, which can confirm a satisfactory stability of ferric oxide electrode. Above results show that the as-prepared ferric oxide materials can make it a promising electrocatalytic electrode in degradation of dye in the wastewater.