ABSTRACT Here, we report an atomic substitution strategy between RuNi‐Alloy and ZIF‐8 to synthesize Ni single‐atom catalyst (SAC) supported on a carbon‐nitrogen framework (CNF), derived via high temperature calcination (900°C) of RuNi‐ZIF‐8. The resulting atomically engineered (RuZn)/Ni‐CN exhibits multifunctional activity for both Nitrate reduction reaction (NO 3 RR) and Oxygen evolution reaction (OER). In NO 3 RR, (RuZn)/Ni‐CN delivers a high ammonia yield of 10199 µg h −1 mg −1 cat with 84% Faradaic efficiency (FE) at −0.9 V vs. RHE. This performance is obtained using a Pt anode in a 0.1 M NaNO 3 solution containing 0.1 m Na 2 SO 4 , following the optimization of pH. (RuZn)/Ni‐CN achieves superior OER performance, with an overpotential of 303 mV at 50 mA cm −2 and exhibits low charge transfer resistance (0.43 Ω) and a small Tafel slope (62 mV/dec), indicating fast reaction kinetics. The TOF reaches 0.3278 × 10 −3 s −1 and retains long‐term operational stability with negligible degradation for 30 h. (RuZn)/Ni‐CN acted as a bifunctional catalyst in cathode and anode and delivered highest ammonia yield and FE of 10123 µg h −1 mg −1 cat and 83%, respectively. EXAFS and structural analyses confirm strong metal‐support interactions, with Ni as coordinatively unsaturated single atoms and minor clusters that synergistically enhance activity.
Jamma et al. (Wed,) studied this question.