I need to coat a piece of aluminum with aluminum oxide. Can I do it by just attaching aluminum to an electrode and put it into some water with the other electrode? I know you can make iron oxide that way, but will aluminum work? If it will work, which electrode should I put the aluminum on?This Site Might Help You. RE: Can you make aluminum oxide by electrolysis? I need to coat a piece of aluminum with aluminum oxide. Can I do it by just attaching aluminum to an electrode and put it into some water with the other electrode? I know you can make iron oxide that way, but will aluminum work? If it will work, which electrode should I put the aluminum on?The way I remember it is a cathode is like a catheter because they both receive stuff and the anode is the opposite of that) So, if you break apart Al2O3 you have 2Al^3+ and 3O^2-. Al^3+ goes to the cathode to receive electrons and become a neutral metal. O^2- goes to the anode to donate electrons and become O2 gas. Hope the analogy and explanation helps!it is called hard anodization a lot of machine shops can do it - I think there is a certain soup to put it in The Al would be the anodeOther related question