Ni‐Fe Nitride Nanoplates on Nitrogen‐Doped Graphene as a Synergistic Catalyst for Reversible Oxygen Evolution Reaction and Rechargeable Zn‐Air Battery

Abstract

Obtaining bifunctional electrocatalysts with high activity for the oxygen evolution reaction (OER) and oxygen reduction reaction (ORR) is a main hurdle in the application of rechargeable metal-air batteries. Earth-abundant 3d transition metal-based catalysts have been developed for the OER and ORR; however, most of these are based on oxides, whose insulating nature strongly restricts their catalytic performance. This study describes a metallic Ni-Fe nitride/nitrogen-doped graphene hybrid in which 2D Ni-Fe nitride nanoplates are strongly coupled with the graphene support. Electronic structure of the Ni-Fe nitride is changed by hybridizing with the nitrogen-doped graphene. The unique heterostructure of this hybrid catalyst results in very high OER activity with the lowest onset overpotential (150 mV) reported, and good ORR activity comparable to that for commercial Pt/C. The high activity and durability of this bifunctional catalyst are also confirmed in rechargeable zinc-air batteries that are stable for 180 cycles with an overall overpotential of only 0.77 V at 10 mA .

Recent Advances toward the Rational Design of Efficient Bifunctional Air Electrodes for Rechargeable Zn–Air Batteries

“…Wang et al replaced the precious Fe 3 Pt with Co, N‐codoped carbon nanoframes (Co, N‐CNF) developing a 3D carbon nanoframe scaffold–immobilized Ni 3 FeN nanoparticle electrocatalyst, wherein, the Ni 3 FeN/Co, N‐CNF hybrid afforded remarkable OER activity (overpotential of 0.27 V, superior to IrO 2 ) and excellent ORR performance (half‐wave potential of 0.81 V vs reversible hydrogen electrode (RHE), superior to Pt/C). Fan et al demonstrated a hybrid catalyst, of which 2D metallic Ni–Fe nitride were strongly coupled with nitrogen‐doped graphene. Electronic structure of the Ni–Fe nitride was changed by hybridizing with the nitrogen‐doped graphene, resulting in a unique heterostructure, leading to very high OER activity with the lowest onset overpotential (150 mV), and competitive ORR activity than commercial Pt/C (Figure d,e).…”

“…d) XRD pattern and atomic force microscopy (AFM) image and cross‐sectional profile and e) bright‐field (BF)‐HRTEM image of the Ni 3 FeN/N‐doped reduced graphene oxide (NRGO) hybrid catalyst. Reproduced with permission . Copyright 2017, Wiley.…”

Highly Active Ternary Nickel–Iron oxide as Bifunctional Catalyst for Electrochemical Water Splitting

“…Thus the development of sufficiently available, low‐cost, highly active OER and/or HER electrocatalyst in alkaline medium is of high demand in the present scenario. Recently, nickel–based electrocatalysts such as oxides, hydroxides, chalcogenides, phosphides, nitrides etc. have exhibited very promising electrocatalytic performance and durability towards OER and/or HER .…”

Toward Promising Cathode Catalysts for Nonlithium Metal–Oxygen Batteries

“…Copyright 2017, Elsevier; and e) HRTEM image of Ni 3 FeN nanoplates on N‐doped graphene (inset: the Fourier transform diffraction pattern). Reproduced with permission . Copyright 2017, Wiley‐VCH…”

“…Practically, functional carbons may still be incorporated with these nitrides to further enhance their electrocatalytic performance . For instance, N‐doped graphene has been employed to support single‐crystal Ni–Fe nitride nanoplates (Figure e) . The combination of Ni–Fe nitride with N‐doped graphene resulted in a high OER activity with a low onset overpotential of 150 mV and an improved ORR stability comparable to that of Pt/C.…”