Ni₃FeN‐Supported Fe₃Pt Intermetallic Nanoalloy as a High‐Performance Bifunctional Catalyst for Metal–Air Batteries

Abstract

Electrocatalysts for both the oxygen reduction and evolution reactions (ORR and OER) are vital for the performances of rechargeable metal–air batteries. Herein, we report an advanced bifunctional oxygen electrocatalyst consisting of porous metallic nickel‐iron nitride (Ni3FeN) supporting ordered Fe3Pt intermetallic nanoalloy. In this hybrid catalyst, the bimetallic nitride Ni3FeN mainly contributes to the high activity for the OER while the ordered Fe3Pt nanoalloy contributes to the excellent activity for the ORR. Robust Ni3FeN‐supported Fe3Pt catalysts show superior catalytic performance to the state‐of‐the‐art ORR catalyst (Pt/C) and OER catalyst (Ir/C). The Fe3Pt/Ni3FeN bifunctional catalyst enables Zn–air batteries to achieve a long‐term cycling performance of over 480 h at 10 mA cm−2 with high efficiency. The extraordinarily high performance of the Fe3Pt/Ni3FeN bifunctional catalyst makes it a very promising air cathode in alkaline electrolyte.

Cobalt‐Based Metal–Organic Framework Nanoarrays as Bifunctional Oxygen Electrocatalysts for Rechargeable Zn‐Air Batteries

“…The XPS survey spectrum disclosed that Co-MOF/GF consisted of Co,O ,a nd Ce lements. [13] Noticeably,t he current density of the Co-MOF/GF reached 10 mA cm À2 at as ubstantially decreased overpotential of % 220 mV,w hich was far lower than 380 mV for the Ir/Ca nd those for the previously reported OER electrocatalysts, for example,N iFe-layered double hydroxide film (NiFe-LDH, 240 mV at 10 mA cm À2 ), [14] NiCo-ultrathinM OFs nanosheets (250 mV at 10 mA cm À2 ), [8a] Fe 3 Pt/Ni 3 FeN ( % 370 mV at 10 mA cm À2 ), [15] Co 3 O 4 nanowire arrays (290 mV at 10 mA cm À2 ), [16] N-doped graphene nanoribbon networks (360 mV at 10 mA cm À2 ), [17] Ni 3 S 2 nanosheets (260 mV at 10 mA cm À2 ), [18] and g-CoOOH nanosheets ( % 300 mV at 10 mA cm À2 ) [19] (Figure 2b,T ableS1). [12] To evaluate the electrocatalytic OER performance of the electrocatalysts, at hree-electrode system in an O 2 -purged 1 m KOH aqueous solutionw as appliedu sing ag raphite rod and an Hg/ HgO electrode as the counter and reference electrodes, respectively.A ll potentials were referenced to the reversible hydrogen electrode (RHE), and the Ohmic potential drop loss caused by electrolyte resistanceh ad been subtracted (Figures S17 and 18).…”

Robust bifunctional oxygen electrocatalyst with a “rigid and flexible” structure for air-cathodes

“…A synergetic combination of oxides with carbon materials is a general strategy for designing efficient bifunctional electrocatalysts [28][29][30][31][32][33][34][35] . Notably, such carbonsupported metal oxides are electrochemically unstable, especially under harsh OER conditions because carbon oxidation/corrosion occurs at relatively low potentials (C + 2H 2 O → CO 2 + 4H + + 4e − , E 0 = 0.207 V vs. standard hydrogen potential) 36,37 . Carbon corrosion has been identified as a main issue that greatly affects the stability of catalysts 11,38 .…”

“…Carbon corrosion has been identified as a main issue that greatly affects the stability of catalysts 11,38 . In this regard, exploring robust carbon-free bifunctional electrocatalysts while retaining satisfactory electrical conductivity and evident catalytic activity is vitally necessary 36,38,39 . For instance, Chen et al developed a new carbon-free bifunctional catalyst comprising CaMnO 3 and Pt clusters (Pt/CaMnO 3 ) that exhibit evidently prolonged durability and optimized activity relative to that of carbonsupported Pt and CaMnO 3 alone 39 .…”

“…A similar result was also observed for a synergetic catalyst of Co 3 O 4 and Ag particles (Ag/Co 3 O 4 ) 40 . More recently, Goodenough et al reported a robust Ni 3 FeN-supported Fe 3 Pt (Fe 3 Pt/Ni 3 FeN) that can enable Zn-air batteries to achieve long-term cycling stability with high efficiency as an air-cathode 36 . Although these robust carbon-free-supported noble metal catalysts become markedly more stable, the morphology and structure of these catalysts are unsatisfactory because electrocatalysis is a type of structure sensitive reaction, especially for ORRs.…”

Precious Metal-Free Nickel Nitride Catalyst for the Oxygen Reduction Reaction

“…31 Ni3FeN nanostructures have shown promising bifunctional activity, both as supports and catalysts, for metal-air batteries in alkaline media. [32][33][34] Additionally, Ni3N quantum dots supported on NiO nanosheets have shown good activity and stability for ORR in alkaline. 35 Herein, we demonstrate an ORR active nickel nitride catalyst in acid for the first time.…”