Electrode, electrode manufacturing process and electrochemical cell

US5419824A · kind A · utility

Inventors

• Oleh Weres · Gardnerville, US
• Michael Hoffmann · Gablingen, DE

Key dates

• Filing date: Feb 10, 1994
• Grant date: May 30, 1995
• Expiry date: Feb 10, 2014

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C02F2305/023
• WIPO field: Environmental technology
• WIPO sector: Chemistry

Abstract

This invention provides a novel electrode which is capable of operation at sufficiently positive anodic potential to produce hydroxyl free radicals and release them into solution, and a process for producing these electrodes. It also provides electrochemical cells utilizing these electrodes, and a novel material included in these electrodes. The electrode consists of titanium metal or a titanium alloy, with an oxide coating that includes titanium dioxide and also includes niobium(IV) oxide or tantalum(IV) oxide, sufficient to impart adequate electrical conductivity to the titanium dioxide under the necessary anodic polarization. An electrode preparation process is described, which allows niobium or tantalum in the oxide coating to be reduced to the +4 valence state, and causes the coating to assume a very stable and insoluble crystal structure. A process for manufacturing ammonium niobate, which is the preferred source compound for niobium in the electrode manufacturing process, is also provided.