N-doped graphene analogue synthesized by pyrolysis of metal tetrapyridinoporphyrazine with high and stable catalytic activity for oxygen reduction

We fabricated N-doped graphene analogue by pyrolysis of metal tetrapyridinoporphyrazine (MTAP), a kind of N rich metal phthalocyanine derivative with four pyridine substituents. The combination results of elemental analysis, X-ray photoelectron spectroscopy and electron-energy-loss spectrometry mapping show that the obtained N-doped graphene analogue is nitrogen-rich and has uniform distribution of C and N atoms. The atomic ratio of N/C in the obtained graphene is about 20.5%. The majority of N atoms are present in a pyridine type environment. Theoretical analysis based on DFT calculations has been performed for a deep understanding of the role of MTAP in the synthesis of the N-doped graphene analogue. Electrochemistry results show the N-doped graphene analogue exhibits a one-step, four-electron pathway for oxygen reduction reaction, and shows almost identical voltammetric responses before and after about 100000 cycles, indicating that it has high and stable electrocatalytic activity for oxygen reduction.