Electrochemical oxidation of cinnamic acid with Mo modified PbO2 electrode: Electrode characterization, kinetics and degradation pathway

A novel molybdenum modified PbO 2 electrode was successfully prepared with the method of electrodeposition . The SEM and XRD were employed to study the surface morphology of electrodes, which indicated that the modified PbO 2 electrode had a larger effective area and more compact film. Electrochemical degradation of cinnamic acid (CA) in aqueous solution with Mo–PbO 2 electrode and PbO 2 electrode were investigated. The results showed that the Mo–PbO 2 electrode had a better effect of CA removal. The operational parameters influencing the electrochemical degradation of CA with Mo–PbO 2 electrode were optimized and the results revealed that the electrochemical degradation of CA followed the pseudo-first-order kinetics and the optimal removal of CA and COD were 85.51% and 25.79% after 120   min on condition of the electrolyte concentration, initial concentration of CA, current density and initial value of pH were 0.1   mol/L, 300   mg/L, 10   mA/cm 2 and 3.4, respectively. The degradation mechanism of CA in electrochemical oxidation with Mo–PbO 2 electrode was analyzed and the main degradation pathway of CA was proposed based on the intermediates identified by IC and GC–MS.