Process for preparing iridium oxide film

• US 5,030,331 A
• Filed: 10/11/1989
• Issued: 07/09/1991
• Est. Priority Date: 11/11/1988
• Status: Expired due to Fees

• Current Assignee: Agency of Industrial Science & Technology (Government of Japan)
• Original Assignee: Agency of Industrial Science & Technology (Government of Japan)
• Inventors: Sato, Yoshiyuki
• Primary Examiner(s): Nguyen, Nam X.
• Application Number:
  US07/420,061
• Time in Patent Office: 636 Days
• Field of Search: 204/38.3, 204/56.1, 204/192.15, 204/192.22, 204/192.29, 427/35, 427/37, 427/38, 427/126.5
• US Class Current: 205/107
• CPC Class Codes: C23C 14/06 characterised by the coating material C23C14/0021 , C23C14/04 take precedence
• CPC Class Codes: C23C 14/58 After-treatment
• CPC Class Codes: C23C 14/5806 Thermal treatment
• CPC Class Codes: C23C 14/5853 Oxidation
• CPC Class Codes: C25D 11/34 of metals or alloys not provided for in groups C25D11/04 - C25D11/32
• CPC Class Codes: G02F 1/15245 based on iridium oxide or hydroxide

Abstract

The present invention provides a process for preparing an iridium oxide film which comprises evaporating iridium and carbon by electron beam or sputtering to prepare an iridium-carbon composite film, heating said composite film in an oxidizing atmosphere to form a thermally oxidized iridium oxide film, and continuously applying an alternating potential to said iridium oxide film in an aqueous solution to conduct electrolytic oxidation.

Claims

1. A process for preparing an iridium oxide film which comprises evaporating iridium and carbon by electron beam or sputtering to prepare an iridiumcarbon composite film, heating said composite film in an oxidizing atmosphere to form a thermally oxidized iridium oxide film, and continuously applying an alternating potential to said iridium oxide film in an aqueous solution to conduct electrolytic oxidation.

2. A process according to claim 1 wherein the atomic ratio of iridium to carbon (Ir :

C) in said iridium-carbon composite film is 0.05 to 0.30.

3. A process according to claim 1, wherein the heating temperature in said oxidizing atmosphere is 225°

to 350°

C.

4. A process according to claim 1 wherein the upper limit and the lower limit of said alternating potential are +1.25 to +1.6 V and -0.1 to +0.25 V, respectively.