An anode catalyst suitable for use in an electrolyzer. The anode catalyst includes a support and a plurality of catalyst particles disposed on the support. The support may include a plurality of metal oxide or doped metal oxide particles. The catalyst particles, which may be iridium, iridium oxide, ruthenium, ruthenium oxide, platinum, and/or platinum black particles, may be arranged to form one or more aggregations of catalyst particles on the support. Each of the aggregations of catalyst particles may include at least 10 particles, wherein each of the at least 10 particles is in physical contact with at least one other particle. The support particles and their associated catalyst particles may be dispersed in a binder.
FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
 This invention was made with government support under DOE SBIR Phase II and Phase JIB Grant No. DE-SC0007471 entitled "High-Performance, Long-Lifetime Catalysts for Proton Exchange Membrane Electrolysis" awarded by the United States Department of Energy. The government has certain rights in the invention.