Molecular design of porphyrin precursors toward thermally stable microporous ordered carbonaceous frameworks for...

Ordered carbonaceous frameworks (OCFs) derived from metalloporphyrins enable atomically dispersed metal sites in conductive carbon, but limited porosity and thermal stability hinder their applications. To address these issues, Fe porphyrin precursors with eight polymerizable ethynyl groups were designed to construct microporous Fe-based OCFs. An ordered framework structure with atomically dispersed Fe sites was obtained after carbonization at 700 °C via cross-linking of ethynyl groups, yielding a high surface area (∼600 m² g^-1) with uniform micropores (∼0.57 nm). The prepared materials catalyse the oxygen reduction reaction via a four-electron pathway, approaching the performance of Pt/C. This work highlights molecular precursor design as a strategy to control atomic dispersion, carbonization stability, and porosity for electrocatalyst applications.