Binary Transition Metal and Nitrogen Functionalised Silicon Oxycarbide Electrocatalysts for Zn–Air Battery Air Electrode Application

The need for the wider adoption of next‐generation energy storage systems due to the usage of renewable energy encourages the development of alternatives to the lithium‐ion battery (LIB) technology. Rechargeable zinc–air battery (RZAB) could meet this objective as affordable, safe, and material abundant alternative if suitable non‐Pt group metal (PGM) air electrode bifunctional catalyst for oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) is developed. Herein, we investigate three binary transition metal (TM) combinations (Fe/Co, Fe/Mn, Fe/Cu) for the polymer‐derived ceramics (PDCs)‐based bifunctional catalyst fabrication. Dicyandiamide (DCDA) was used as a nitrogen source for the dual TM‐containing PDC material modification. The highest electrocatalytic activity towards the ORR/OER in 0.1 and 1.0 M KOH was witnessed in the case of Fe/Co‐containing material (Fe/Co‐PDC‐N, ORR/OER potential gap in 0.1 M KOH of 0.87 V), which was also the most promising non‐PGM catalyst in the RZAB configuration. Fe/Co‐PDC‐N showed the maximum power density of 142 mW cm −2 , 46 h lifetime for 10 mA cm −2 charge–discharge cycling and 97% depth of discharge (DoD). Comparative RZAB measurements were performed with the commercial Pt‐Ru/C catalyst drawing attention to the performance enhancement implemented by the RZAB cell design modifications.