Electronic Configuration Regulation by N-Doped MXenes Boosting Electrocatalytic Performance of Cobalt Phthalocyanine

Graphical Cobalt phthalocyanine was supported on N-doped MXene via axial coordination and π-π stacking. The formed axial coordination configuration N−Co−N 4 can effectively break the planar structure of Co-N 4 and enhance the oxygen reduction performance with an E 1/2 of 0.863 V, which is better than the 20 wt.% Pt/C catalyst of 0.85 V. The precise control of electronic configurations of catalytic sites via molecular engineering is significantly desirable for boosting electrocatalytic activity. We reported a new-type composite electrocatalyst with cobalt phthalocyanine supported on N-doped MXene nanosheets (N-MXene/CoPc) through a self-assembly process. Beneficial from the joint action of N sites participation and axial coordination, N-MXene/CoPc exhibits a high ORR activity with positive onset potential (E onset =0.98 V vs. RHE) and half-wave potential (E 1/2 =0.863 V), which is superior over the pristine CoPc (E 1/2 =0.72 V) and the composite with undoped MXene as support (MXene/CoPc, E 1/2 =0.771 V). Additionally, N-MXene/CoPc exhibits an excellent durability with only 8.5 % attenuation after 25000 s of continuous i-t test, while a more obvious decay 18.6 % for 20 wt.% Pt/C. This work not merely reported a robust ORR catalyst, but more provides a reasonable design strategy for nonnoble-metal catalysts through catalyst-support interactions.