Nitrogen and sulfur co-doped fibrous-like carbon electrocatalyst derived from conductive polymers for highly active oxygen reduction catalysis

Abstract Carbon-based electrocatalysts hold great promise towards the development of clean renewable energy conversion and storage technologies. Herein, we present the preparation of a nitrogen (N) and sulfur (S) co-doped fibrous-like carbon electrocatalyst through sequential polymerization of conjugated poly(3,4-ethylenedioxythiophene) and polyaniline polymers onto silica nanoparticles, followed by carbonization. The morphological characterization of the material reveals a highly entangled fibrous-like carbon structure after etching away of the silica nanoparticles. The as-obtained N and S co-doped entangled fibrous-like carbon electrocatalyst demonstrates excellent oxygen reduction reaction (ORR) activity with an onset potential of 0.94 V vs. RHE, comparable to the onset potential 1.0 V vs. RHE of benchmark Pt/C (20 wt%) and outperforming single heteroatom (N/S) doped carbon in alkaline medium. The catalyst also shows excellent stability and resistance towards methanol poisoning effects. This study demonstrates the facile synthesis of N and S co-doped fibrous-like carbon-based catalysts for ORR derived from conjugated polymers as a potential alternative to precious metal-based catalysts.