Hierarchically porous aggregates of Co–N–C nanoparticles for oxygen electrocatalysis

Herein, a novel assembled Co–N–C (A–Co–N–C) material was reported for the first time by pyrolyzing zeolitic imidazolate framework-67 (ZIF-67) nanoparticle aggregates caused by the introduction of surfactant polystyrene sulfonic acid (PSS).