FeNi₂Se₄–Reduced Graphene Oxide Nanocomposite: Enhancing Bifunctional Electrocatalytic Activity for Oxygen Evolution and Reduction through Synergistic Effects

Abstract

Water splitting reaction using earth abundant and environmentally benign catalysts is critical for renewable energy technologies. Herein we report a hybrid composite, FeNi 2 Se 4 nanoparticles supported on nitrogen doped reduced graphene oxide (FeNi 2 Se 4 -NrGO) as an efficient and dependable bifunctional electrocatalyst for oxygen evolution and oxygen reduction reactions (OER and ORR, respectively) under alkaline conditions. While FeNi 2 Se 4 nanoparticles themselves showed good catalytic activity for water oxidation, the constructed hybrid nanocomposite with NrGO as the supporting matrix, showed enhanced catalytic activity with a small overpotential of 170 mV @ 10 mAcm -2 , small Tafel slope of 62.1 mV/decade, and high current density. The ORR catalytic activity of This article is protected by copyright. All rights reserved. 2 the nanocomposite catalyst was also good with an onset potential of 0.93 V. This is possibly due to the synergistic chemical coupling effects between the FeNi 2 Se 4 and NrGO matrix.Chronoamperometric studies showed that the catalyst is stable under conditions of continuous O 2 evolution and reduction with very less degradation. Apart from reporting highly efficient OER-ORR bifunctional catalyst, this study also provides more proof for the effect of anion coordination on the catalyst performance, as well as the synergistic role of nanoscale interactions between the catalyst particles and graphene matrix to enhance catalytic activity.

Hexagonal FeNi2Se4@C Nanoflakes as High Performance Anode Materials for Sodium-ion Batteries

“…The pattern exhibits a group of distinct diffraction peaks, which can be well assigned to a monoclinic FeNi2Se4 phase (PDF#04-006-5240) [31,32] , indicating the high crystallinity and purity of the synthesized product. The SEM images of FeNi2Se4@C are shown in Fig.…”

Well‐Monodispersed Iron‐Doped InOOH Nanoparticles with Enhanced Activity for Oxygen Evolution

“…Besides, we further normalized current density by the ECSA and the ECSA is evaluated by C dl in terms of the equation: ECSA = C dl /C s . [47] Figure 3f present the normalized OER LSV curves of Fe-InOOH, FeOOH and InOOH by ECSA, the normalized activity of Fe-InOOH catalyst still shows much higher than that of InOOH, indicating that the factors other than the ECSA also related to the enhanced OER activity, which can attribute to the strategy of Fe doping enhances the intrinsic activity toward OER not just increases the active surface area. To probe and compare the intrinsic activity of Fe-InOOH with other electrodes, the turnover frequency (TOF) for each active site of Fe-InOOH, InOOH and FeOOH were measured at 50 mV s À 1 in 1.0 M solution PBS (pH = 7.0), as shown in ( Figure S8).…”

“…The Fe‐InOOH catalyst has a larger electrochemically active surface area and can provide more active sites exposed to the electrolyte, which is compatible with the above‐mentioned results. Besides, we further normalized current density by the ECSA and the ECSA is evaluated by C dl in terms of the equation: ECSA=C dl /C s . Figure f present the normalized OER LSV curves of Fe‐InOOH, FeOOH and InOOH by ECSA, the normalized activity of Fe‐InOOH catalyst still shows much higher than that of InOOH, indicating that the factors other than the ECSA also related to the enhanced OER activity, which can attribute to the strategy of Fe doping enhances the intrinsic activity toward OER not just increases the active surface area.…”

Oxygen Reduction Reaction in the Field of Water Environment for Application of Nanomaterials

“…In terms of mechanism research, good development has not been achieved [68]. The main reason is that in the aqueous environment among others, the relationship between the solid phase catalyst, the oxidant, and the target reactant is complicated, and, currently, no studies have been able to provide explicit information on the relationship between the three in the reaction process [83,84]. Under such circumstances, although the developed effective catalyst can achieve the conditions of high efficiency and low energy consumption, it is usually accompanied by disadvantages such as many components, high cost, and complicated preparation.…”