(1) Coating solution, the coating solution is coated on the surface of
titanium matrix, usually using brush coating method, can also use electrostatic spraying method, roller coating method.
(2) drying, each coating once in the infrared lamp, or far infrared lamp baking, drying temperature is generally in 100-200 ℃, so that the solvent slowly volatilized. Drying process is to volatilize all the solvent, if the volatilization is not complete, with the thermal oxidation process, will affect the coating adhesion and electrochemical performance of the electrode.
(3) Thermal oxidation, calcination in the heating furnace at the specified temperature for 10 to 15 min. On the one hand, the chlorine content in the coating decreases to a very low level, and the conductivity of the coating deteriorates. On the other hand, the oxide crystal becomes larger, the grain is too large to make the coating.
The decrease of binding force leads to the deterioration of electrochemical performance.
The thermal oxidation temperature is too low, the oxidation is incomplete, the binding force is poor, and the required electrocatalytic performance is not obtained.
The oxidation temperature affects the structure, composition and properties of the coating, generally above 400℃, RuO2 and TiO2 solid solutions with rutile structure can be obtained.
When the coating is platinum group metal oxides, such as RuO2, the heating atmosphere must be oxidizing and the reducing atmosphere is not suitable.
