Characteristics of Boron-Doped Diamond Electrodes Deposited on Titanium Substrate with TiN _x Interlayer

A Boron-doped diamond (BDD) layers and the titanium nitride (TiN _x ) interlayers were prepared by hot filament chemical vapor deposition (HFCVD) and reactive DC magnetron sputtering, respectively. The TiN _x interlayer was introduced between the BDD film and the Ti substrate to improve the adhesion between substrate and film. BDD film on the etched Ti substrate was well deposited, but sample had partial delamination from the Ti substrate after 24 h. However, BDD/TiN _x /Ti samples did not show delamination after 24 h. In cyclic voltammetry results, BDD/TiN _x (5, 10% N₂)/Ti electrodes has wide potential windows of ~3 V and samples did not occur leakage current. The X-ray diffraction results confirmed that the BDD film was deposited on the Ti substrate without TiN _x interlayer showed a highest TiC (002) peak, which contributes to peeling from the substrate. However, the TiC (002) peak was not observed for the BDD film with a TiN _x interlayer (5% N₂) deposited on a chemically etched Ti substrate. As a result, adhesion of BDD was remarkably improved by both the TiN _x interlayer and chemical etching pre-treatment. The BDD/TiN _x (5% N₂)/Ti prepared in this study also showed enhanced performance compared to BDD/Nb for chemical oxygen demand (COD) decomposition of approximately 92%.