Fabrication and Electrochemical Properties of High Doped-Si/BDD Thin-Film Electrode

Boron-doped diamond(BDD) thin film is a new electrode material that has received great attention recently owe to its possessing unique characteristics.Boron-doped diamond film on the heavily doped silicon substrate was prepared by the microwave plasma chemical vapor deposition.The electrochemical properties of BDD were characterized by resistivity measurement by 4-point probe method,SEM,Raman spectroscopy and electrochemistry working station.The resistivity of diamond films is 10-2Ω·cm,Meanwhile,the quality of the diamond film was deteriorated with the increasing of boron doped.The electrochemical properties of the electrode were investigated using cyclic voltammetry,The results showed that Si/BDD electrode had a very wide potential window(2.8~3.2V)and very low background current(-3×10-6~2×10-6A),comparing with Pt electrode(1.8V and-1×10-3~3×10-4A);and as electrode leader for BDD was jointed to the conducting substrate(high doped-Si),more work area and lower cost of BDD could get.In electrolyte including Ferri/Ferrocyanide,the electrochemical reaction was carried out on the surface with good quasi-reversibility and excellent chemical stability.Studies of the oxidation of organic compounds showed that,comparing with Pt electrode,the diamond electrode could oxidate phenol,and the process of oxidation was very simple and complete.