as an innovative disinfectant characterized by its high efficiency
broad antimicrobial spectrum
and non-toxic residues
has been broadly used in health care industry
medicines
agriculture
and food processing. EOW is usually generated by electrolysis of a dilute NaCl solution in a chamber with two cells separated by membrane
and is obtained from the anode side. But low current efficiency and short service life of the anode in EOW generators restrict the application of EOW. Ir0.5Pt0.5O2 anode was prepared by the improved Adams fusion method. The properties of Ir0.5Pt0.5O2 anode was investigated with X-ray diffraction (XRD)
scanning electron microscope (SEM) and electrochemistry cyclic voltammetry (CV). The crystal type is rutile with (101)
(002) and (301) crystal planes. A large number of cellular structures were observed on the surface of the anode
which greatly increased specific surface area of the anode. With increasing specific surface area
electric charge was enhanced to 0.4 mC
which was 2.65 times of pure IrO2. Electrochemical characteristics of the anode surface
such as oxidation peaks at 1.0 V(Pt-OH) and 0.9 V(Ir3+/Ir4+) proved the formation of platinum iridium oxide. The activities of chlorine evolution and oxygen evolution were also studied through linear sweep voltammetry (LSV). Compared with IrO2
chlorine evolution activity in unit apparent surface area increased significantly
but oxygen evolution activity decreased obviously. The slope of Tafel was 56.3 mV·dec1- for chlorine evolution reaction (CER)
and the mechanism was Volmer-Heyrovsky in which the rate controlling step was electrochemical desorption. The slope of Tafel was 126.6 mV·dec1- for oxygen evolution reaction (OER)
and the rate controlling step was formation of surface hydroxide on the catalyst surface. Electrochemical surface structure and electrochemical performance of Ir0.5Pt0.5O2 oxide coatings in 1 g·L-1 NaCl solution were investigated with electrochemical impedance spectroscopy (EIS). CER activity of Ir0.5Pt0.5O2 was better than IrO2
which was in agreement with previous research. In the actual EOW preparation
electrolysis efficiency and available chlorine content (ACC) of EOW on the Ir0.5Pt0.5O2 anode were much greater than IrO2 anode under the same condition. The accelerated life of Ir0.5Pt0.5O2 anode was 3.14 times of the IrO2 anode and the performance of the anode was greatly improved