Template–Free–Induced Synthesis of an Fe–N–C Electrocatalyst with Porous Yolk–Shell Structure Towards Oxygen Reduction Reaction

Significant research has focused on cost–effective, highly active, and exceptionally stable non–noble metal electrocatalysts (NNMEs) to boost the performance of the oxygen reduction reaction (ORR). Of note, the development of design and synthesis of Fe–N–C electrocatalysts is essential but remains challenging. Herein, the Fe and N co–doped porous carbon material with a yolk–shell (YS) structure, termed SA–H2TPyP@PDA–Fe (900), was fabricated by self–assembly of metal–free porphyrin as a yolk and polymerization of dopamine as a shell with an addition of iron salts, followed by the high–temperature pyrolysis and acid–leaching. As a result, active sites, like FeN4 and N–doped C, within rich porous YS carbon structures, play an important role for ORR in an alkaline media. The SA–H2TPyP@PDA–Fe (900) electrocatalyst shows positive ORR performances than those of SA–H2TPyP (900) and SA–H2TPyP@PDA (900), indicating the dominating function of the YS carbon structure decorated with Fe–based species. This efficient route of template–free–induced preparation of the YS structure discovers the design and synthesis of NNMEs for ORR.