|MadSci Network: Chemistry|
Hydrogen peroxide in higher concentrations (>70%) is easily decomposed. That is part of the reason it is considered an extremely dangerous rocket fuel and is no longer used. Several catalysts including various permanganates, manganese dioxide, platinum and iron oxide have been used successfully to facilitate the decomposition. If a flake of rust gets into the hydrogen peroxide fuel, it can start the decomposition. So be careful!
Depending on your design, you may be able to simply use a steel chamber and oxidize the inside to give you an iron oxide catalyst for the decomposition. Platinum coatings are available commercially and should not be too expensive. All you need is a few micrometers deposited on the interior of the chamber.
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