Insight on the active sites of CoNi alloy embedded in N-doped carbon nanotubes for oxygen reduction reaction

Transition metal alloy electrocatalysts have sparked intense interest for their use in oxygen reduction reaction (ORR). However, there is almost no corresponding research on the active sites. In this study, CoNi nanoparticles embedded bamboo-like N-doped carbon nanotubes (CoNi-NCTs) as catalysts constructed by a facile pyrolysis of Prussian blue analogs were investigated. The density functional theory calculation reveals that molecules are more easily adsorbed Ni sites these catalysts, while Co favor formation OOH⋆ intermediates during ORR. addition, cooperation alloys with benefits electron transfer and promotes electrocatalytic activity. optimized CoNi-NCT shows remarkable ORR catalytic activity an half-wave potential (E1/2) 0.83 V, onset (Eonset) 0.97 superior durability, all which surpass commercial Pt/C catalysts. assembled zinc-air battery delivers small charge/discharge voltage gap 0.86 V at 10 mA cm−2, high-power 167 mW good stability (running stably over 900 cycles).