Abstract: Hydrophobic Cu-polytetrafluoroethlyene(Cu-PTFE) and Zn-PTFE composite electrodes were prepared by composite electroplating with copper and zinc as substrates, respectively. The electrochemical reduction behavior of benzoic acid on hydrophobic composite electrodes was studied. The electrochemical parameters such as Tafel polarization curve, cyclic voltammogram(CV), electrode stability and electrochemical impedance spectroscopy(EIS) were investigated. The results show that the Cu-PTFE composite electrode possesses a higher catalytic activity in the preparation of benzaldehyde from benzoic acid than that of Zn-PTFE composite electrode, the yields of the electrochemical reduction on Cu-PTFE and Zn-PTFE composite electrodes are 88.4% and 79.2%, respectively. The Cu-PTFE composite electrode is promising as an electrode for preparation of benzaldehyde via electrochemical approach. The result shows that the electrochemical reduction of benzoic acid on the composite electrodes may be exclusively controlled by electron transfer process.

Key words: hydrophobic composite electrode, benzoic acid, electrochemical reduction behavior, benzaldehyde