Optimized Synthesis of Fe/N/C Cathode Catalysts for PEM Fuel Cells: A Matter of Iron-Ligand Coordina
It's all in the detail: Highly active Fe/N/C catalysts for the oxygen-reduction reaction in polymer-electrolyte-membrane (PEM) fuel cells can be obtained from a precursor constructed from the zeolitic imidazolate framework ZIF-8 and an iron–ligand complex if, and only if, the displacement of ZnII ions from ZIF-8 by FeII ions is restricted (see picture; TPTZ=2,4,6-tris(2-pyridyl)-s-triazine).