Structure and electrochemical behavior of nitrogen doped diamond-like carbon thin films with or without platinum and ruthenium doping

• Main Author: Khun, Nay Win
• Other Authors: Zeng Xianting
• Format: Theses and Dissertations
• Language: English
• Published: 2011
• Subjects: DRNTU::Engineering::Materials::Microelectronics and semiconductor materials
• Institution: Nanyang Technological University

Human activities have released toxic metals such as Zn, Pb, Cd, Cu and Hg, etc. into the environment. Nowadays, the presence of toxic metals in the aquatic ecosystem implicates directly to biota and indirectly to human beings. Therefore, fast detection and determination of toxic metals in aqueous solutions are a tough challenge for analysts. Diamond-like carbon (DLC) is a type of carbon, which consists of both sp2 (graphite like) and sp3 (diamond like) bonds, and an environmentally friendly material. In addition, DLC films can be produced at room temperature and achieve similar properties to those of diamond films, so they have been explored as electrode materials for heavy metal tracing. However, high electrical resistivity of DLC films has confined their electrochemical applications. DLC films used as electrodes for electrochemical applications must be conductive. Nitrogen is an effective donor in DLC films because of its five valance electrons. Therefore, nitrogen is used as a dopant for making conductive nitrogen doped diamond-like carbon (N-DLC) films. However, an incorporation of nitrogen in DLC films lowers the corrosion resistance of DLC films by degrading sp3-bonded cross-linking structure through increased sp2 bonds though it can increase the electrical conductivity of the films. Poor corrosion resistance of N-DLC films can affect the electrochemical performance of the films such as sensitivity, long-time response stability, durability and repeatability.