Conjugated microporous polymer derived hierarchically porous N-rich nanocarbon as a durable electrocatalyst for oxygen reduction reaction in Zn-air battery

Nitrogen (N)-doped carbon materials with porous structures are widespread in electrocatalysis for clean energy and environmental remediation applications. However, the synergistic design of hierarchical porous structures and active sites remains challenging. Here, we present a facile and general strategy of using conjugated microporous polymers (CMPs) as the precursors to create in-situ N-doped nanocarbon electrocatalysts through high-temperature pyrolysis. The obtained hierarchically porous carbon sample of TEPT-TA-800 can retain the nanoparticle morphology and high porosity after carbonization and demonstrates exceptional oxygen reduction reaction (ORR) performance with a positive onset potential of 0.94 V vs. RHE and half-wave potential of 0.85 V vs. RHE in an alkaline electrolyte. Theoretical calculations reveal that with the presence of triazine rings, the binding affinity of the ORR intermediates (*OOH, *O, and *OH) and the stability of adsorbed oxygen on TEPT-TA-800 can be improved, which positively impacts the ORR process. Furthermore, TEPT-TA-800 serves as the cathode to construct a Zn-air battery (ZAB), which exhibits superior peak power density (143.1 mW cm −2 ), higher specific capacity (792 mAh/g), and longer-lasting stability (650 h) compared with Pt/C-based ZAB. These findings provide valuable insights into rationally designing CMP-derived carbon materials for various catalysis reactions and energy conversion applications.