Utilization of Deposited Coke on Zeolites During the Catalytic Cracking of Nitrogen‐Containing Polymer for the Oxygen Reduction Reaction

Abstract This work focuses on the development of a new method to utilize deposited coke on zeolite catalysts, formed during the plastic waste cracking. Nitrogen‐doped carbon catalysts are prepared using nylon‐66 and Zn²⁺ ion‐exchanged ZSM‐5 zeolites. After the cracking reaction, nitrogen‐doped carbon materials are obtained by removing zeolites from zeolite/coke composites using base and acid treatment. The synthesized N‐doped carbon using Zn²⁺ type ZSM‐5 zeolites exhibits higher catalytic performance on the oxygen reduction reaction (ORR) with an onset potential of 0.95 V (vs RHE) and a half‐wave potential of 0.80 V (vs RHE) than that using H⁺ type ZSM‐5 zeolites. The characterization revealed that the evaporation of Zn²⁺ in zeolites significantly enhanced the porosity of N‐doped carbon. Moreover, the aromatization and poly‐cyclization reactions promoted the generation of highly active edge Valley‐N sites, leading to their outstanding activity on ORR. This work provides new directions for the utilization of deposited coke on zeolites.