Thermal Synthesis of FeNi@Nitrogen-Doped Graphene Dispersed on Nitrogen-Doped Carbon Matrix as an Excellent Electrocatalyst for Oxygen Evolution Reaction

Abstract

The fabrication of non-precious-metal and highly active electrocatalytic materials to drive oxygen evolution reaction (OER) at low overpotential from earth-abundant elements by a low-cost and easy method is extremely important for many advanced energy technologies. Herein, a non-noble-metal catalyst with FeNi@nitrogen-doped graphene dispersed on a nitrogen-doped carbon matrix (named FeNi@NGE/NC) is synthesized by a facile one-pot pyrolysis process. In this composite, FeNi alloy nanoparticles encapsulated with few-layer nitrogen-doped graphene are uniformly anchored on a nitrogen-doped carbon matrix. The FeNi@NGE/NC composite exhibits outstanding electrocatalytic performance for OER with a low overpotential of 275 mV at 10 mA cm–2, a small Tafel slope of 41.2 mV dec–1, and high stability in 1 M KOH solution. Even at the low concentration of basic solution (0.1 M KOH), it still displays good activity for OER with an overpotential of 372 mV at 10 mA cm–2. The outstanding OER performance of the FeNi@NGE/NC composite can be mainly attributed to the fast electron transfer from the FeNi alloy to nitrogen-doped graphene shells and the high structural stability due to the protection of graphene shells and the carbon matrix. This work may open a facile and low-cost way for large-scale synthesis of non-noble metals/nitrogen-doped carbon composite electrocatalysts for practical application.

Catalyst overcoating engineering towards high-performance electrocatalysis

“…2.2.2 Direct pyrolysis of metal-polymer composites or metal-coordinating organic complexes. Polymers such as PDA, [90][91][92]95,96 polyvinyl pyrrolidone (PVP), 97,98 resin 99 and Ppy [100][101][102][103] have strong metal chelation ability to trap metal ions through their functional groups. The direct pyrolysis of metalpolymer composites in the absence of carbon support provides another route for engineering carbon nanoshell-overcoated electrocatalysts.…”

“…134 Such a synergistic effect was also observed in single-walled CNT-embedded FeCo NPs 323 and FeNi@N-doped graphene. 98 Furthermore, the changes in alloy composition (i.e. FeCoNi alloy) by incorporating a third metal into a binary alloy could tune the electron transfer numbers between metal alloy and overcoated graphene layer; 324 thus, the adsorption of surface intermediates was manipulated to achieve enhanced OER properties.…”

Rechargeable Zn–Air Batteries with Outstanding Cycling Stability Enabled by Ultrafine FeNi Nanoparticles-Encapsulated N-Doped Carbon Nanosheets as a Bifunctional Electrocatalyst

“… Moreover, the incorporated Fe/Ni led to the formation of FeNi and M–N x active sites that have been proved to facilitate the ORR process compared to the N–LCN electrocatalyst (Figure S14 and Table S1). ,, Notably, in comparison to FeNi/N–LCN, the extent of ORR activity increasing was smaller for the Fe/N–LCN and Ni/N–LCN electrocatalysts due to the lack of synergistic effect between Fe and Ni. ,,, The lowest ORR activity of FeNi/N–B–C electrocatalyst can be ascribed to the particulate-shaped structure together with its lowest S BET (Table S2), signifying the important scaffolding effect of melamine.…”

FeNi nanoparticles on Mo2TiC2Tx MXene@nickel foam as robust electrocatalysts for overall water splitting

“…In addition, MXenes are considered as potential electrocatalysts for HER due to their metallic conductivity, rich tunable surface chemistry, and atomic thickness with highly exposed active sites [22][23][24][25]. While transition metals, especially NiFe based nanomaterials, have tunable surface geometry/electronic structures that enable them to be efficient electrocatalysts for OER [26][27][28][29]. Therefore, integrating MXene with NiFe nanoparticles (NPs) should be a feasible strategy to construct overall water splitting electrocatalysts.…”