I've been trying to build a closed system water electrolyser with easily available materials which allows me to collect the gases separately. To do so, I've been meaning to build an acrylic housing with a textile separator in the middle of two compartments which houses the anode and cathode. The purpose of this is to allow the electrolyte to pass through while leaving the gases separate. I want to build a setup that creates a lot of gas so I don't have to wait hours until i get a liter of gas, so the electrodes will be about 6in x 6in in surface. The problem I've been having with this project though is selecting the correct electrode material. I have very low monetary resources so I'd like to get some help on this topic before I buy any more materials that would turn out to be a mistake. I first looked at stainless steel, but I've learned that this produces hexavalent chromium in the electrolyte which can be toxic, so i'd like to avoid that if possible. Also, I question the durability of stainless steel in the long term. I looked into graphite electrodes, but I'm unsure whether the material is capable of withstanding oxygen production without disintegrating within a couple hours of use. I did some tests with grafoil before investing in isomolded plates; it works well, the quantity of gas produced for a given voltage(5 or 12 volts, as i'm using a computer power supply to power my electrolysis tests) is pretty high, but the "foil"(more like paper)takes water and gets soggy and the graphite erodes really fast and just floats everywhere. Should I expect similar results with graphite electrode plates? Last thing i looked into is platinum electrodes, which seem to be the best for this application. They don't corrode, they don't erode, they seem to enable gas production the most and they are prohibitively expensive. Would platinized titanium electrodes work just as well without degradation? Are there any voltage/amperage considerations? Any insight into this topic would be much appreciated.