IrO x · n H 2 O with lattice water–assisted oxygen exchange for high-performance proton exchange membrane water electrolyzers

The trade-off between activity and stability of oxygen evolution reaction (OER) catalysts in proton exchange membrane water electrolyzer (PEMWE) is challenging. Crystalline IrO 2 displays good stability but exhibits poor activity; amorphous IrO x exhibits outstanding activity while sacrificing stability. Here, we combine the advantages of these two materials via a lattice water–incorporated iridium oxide (IrO x · n H 2 O) that has short-range ordered structure of hollandite-like framework. We confirm that IrO x · n H 2 O exhibits boosted activity and ultrahigh stability of >5700 hours (~8 months) with a record-high stability number of 1.9 × 10 7 n oxygen n Ir −1 . We evidence that lattice water is active…

• AI
  Australian Institute of Nuclear Science and Engineering
• AS
  Australian Synchrotron
• UO
  University of Adelaide
• CS
  China Scholarship Council
• WU
  Wuhan University
• WU
  Wuhan University of Technology