NiTiP-Coated Ti as Low-cost Bipolar Plates for Water Electrolysis with Polymer Electrolyte Membranes

Use of hydrogen produced with a renewable energy could help to mitigate problems associated with global warming. There is hence a need to increase use of hydrogen as a fuel, and for that reason, use of household fuel cells and vehicles powered by fuel cells has been increasing rapidly in recent years. Here we report the result of an effort to produce low-cost hydrogen in a polymer electrolyte membrane (PEM) water electrolysis cell. We found that Ti bipolar plates coated with nickel titanium phosphide (NiTiP) could be substituted for the Pt-coated Ti bipolar plates that are generally used in PEM water electrolysis systems, and we report here the efficacy of NiTiP-sputtered Ti bipolar plates in such systems. We found that in most comparisons with reported results, the efficiency of water electrolysis was higher with NiTiP-sputtered Ti bipolar plates than with bipolar plates coated with precious metals. NiTiP-sputtered Ti plates had a very low and constant resistance before and after voltage application.