3,5-Diamino-1,2,4-triazole as a Nitrogen precursor to synthesize highly efficient Co-N/C non-precious metal bifunctional catalyst for oxygen reduction reaction and oxygen evolution reaction

• An effective non-precious metal bifunctional catalyst Co-N/C had been synthesized.
• 3,5-Diamino-1,2,4-triazole (Hdatrz) was used as a Nitrogen precursor.
• The optimal Co-Hdatrz weight percentage and thermal treatment temperature were 30% and 600 °C.
• The Co-N30%/-600 catalyst exhibits high activity and excellent stability towards ORR and OER.
• The Co-N30%/-600 catalyst can be used as a promising catalyst for energy related applications.

Nowadays, the exploration of highly active and cost-effective bifunctional catalysts for oxygen electrode reactions is crucial for various energy conversion applications. Herein, to obtain a highly effective Co-N/C non-precious metal bifunctional catalyst, 3,5-diamino-1,2,4-triazole (Hdatrz) was used for the first time as a Nitrogen precursor. Different Co-Hdatrz complex weight percentages and thermal treatment temperatures had resulted in varying catalyst performance. Among the resulting catalysts, due to the highest active N content, the smallest charge transfer resistance and the synergy of CoO with carbon black, the Co-N30%/C-600 catalyst (the Co-Hdatrz complex weight percentage was 30% and the thermal treatment temperature was 600 °C) demonstrated the highest catalytic activity towards oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) in alkaline medium, which was superior to Pt/C. Additionally, the Co-N30%/C-600 catalyst also showed excellent methanol tolerance and ORR and OER stabilities compared to Pt/C. Thus, the Co-N30%/C-600 catalyst may serve as a promising bifunctional electrocatalyst in fuel cells, metal-air batteries and water splitting cells.