Quasi-Fe-/Zn-phthalocyanine polymer derived 2D FeNC single-atom catalyst for highly efficient ORR and H2O2 sensing

A novel two-dimensional (2D) single-atom Fe/N/C catalyst (Fe 1 Zn 30 NC PDI ) has been prepared upon pyrolyzing a well-designed quasi-Fe-/Zn-phthalocyanine-based polymer (qFePc 1 @qZnPc 30 @PDI). In the qFePc 1 @qZnPc 30 @PDI precursor, qFePc moieties containing Fe-N 4 sites are efficiently segregated by lots of qZnPc moieties connected together by perylene linkers, which not only leads to the larger specific area in the resulting Fe 1 Zn 30 NC PDI but more importantly ensures the in-situ formation of Fe-N 4 sites on the self-supporting 2D N-doped carbon backbone. Impressively, Fe 1 Zn 30 NC PDI exhibites its superior oxygen reduction reaction (ORR) electro-catalytic activity and peroxidase (POD)-like activity. For ORR in an alkaline medium, it exhibites a much higher onset potential of 0.97 V and half-wave potential of 0.89 V than 20 wt% Pt/C catalyst with good durability of 92 % retention rate after 20000 s. And, Fe 1 Zn 30 NC PDI also shows better peak power density (86 mW cm −2 ) compared with 20 wt% Pt/C in Zn-air battery. Benefiting from the specific POD-like activity of Fe-N 4 , the Fe 1 Zn 30 NC PDI also shows excellent and selective performance in colorimetric H 2 O 2 sensing, with the ultrafast response (30 s), a low limit of detection (10 nM), and good robustness. This work sheds light on a promising design concept for synthesizing 2D polymer-derived single-atom multifunctional catalysts.