To form at least either one of hydrogen and oxygen by photolyzing water by anodically oxidizing a member of which the surface is composed of titanium in an electrolyte soln. containing glycerophosphate and one or more kind of metal acetate respectively in specific concns.
Metal ions of a metal acetate are stably formed under high voltage while taken in an anodically oxidized film by using an electrolyte containing 0.06-0.2mol/l of glycerophosphate and 0.011mol/l of the metal acetate to easily form a relatively thick titanium-containing, oxide film or metal doped titania film with a thickness of several μm. Voltage is pref. within a range of 100-400V and, from a point of time when voltage is ready to exceed 100V, spark discharge is generated on the surface of an anode and the oxide film is locally heated to an extremely high temp. The heating of the film is innumerably repeated as mentioned above and, as a result, the crystallization of the, whole of an anodically oxidized film and the taking in of metal ions are performed at the same time.
SHINOHARA KIYOAKI
ISHIZAWA HITOSHI
