A high activity nitrogen-doped carbon catalyst for oxygen reduction reaction derived from polyaniline-iron coordination polymer

•A nitrogen-doped carbon catalyst derived from PANI-iron coordination polymer.•Fe was uniformly distributed in precursor by coordination between Fe3+ and PANI.•N/C/Fe-c catalyst exhibits comparable diffusion-limited current density to Pt/C.

A nitrogen-doped carbon catalyst with trace iron (N/C/Fe-c, 0.54 wt.% Fe) has been prepared through pyrolysis of polyaniline (PANI)-iron coordination polymer. Electrochemical results demonstrate that N/C/Fe-c catalyst displays excellent oxygen reduction reaction (ORR) catalytic activity and shows almost the same diffusion-limited current density for ORR as Pt/C catalyst in acid media. FTIR and XPS measurements indicate that Fe3+ ions coordinate with N atoms of the PANI chains and N/C/Fe-c has a high ratio of graphitic N, which are responsible for high ORR activity.

Graphical abstractThe coordination between Fe3+ ions and N atoms of the PANI chains leads to homogenous distribution of Fe in the PANI-iron coordination polymer. N/C/Fe-c catalyst obtained by chemical coordination exhibited much higher ORR activity than N/C/Fe-p catalyst obtained by physical mixing in acid media.Figure optionsDownload full-size imageDownload as PowerPoint slide