Promising Electrocatalytic Water and Methanol Oxidation Reaction Activity by Nickel Doped Hematite/Surface Oxidized Carbon Nanotubes Composite Structures. Issue 5 (2nd May 2022)

• Record Type: Journal Article
• Authors: Malik, Bibhudatta; Majumder, Sumit; Lorenzi, Roberto; Perelshtein, Ilana; Ejgenberg, Michal; Paleari, Alberto; Nessim, Gilbert Daniel
• Is Part Of: ChemPlusChem. Volume 87:Issue 5(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2022-05-02
• Subjects: carbon nanotubes -- electrochemistry -- methanol oxidation reaction -- Mott-Schottky catalysts -- oxygen evolution reaction; Chemistry -- Periodicals; 540.5
• DOI: 10.1002/cplu.202200036
• Languages: English
• ISSNs: 2192-6506

Abstract

Abstract: Tailoring the precise construction of non‐precious metals and carbon‐based heterogeneous catalysts for electrochemical oxygen evolution reaction (OER) and methanol oxidation reaction (MOR) is crucial for energy conversion applications. Herein, this work reports the composite of Ni doped Fe2 O3 (Ni−Fe2 O3 ) with mildly oxidized multi‐walled CNT (O−CNT) as an outstanding Mott‐Schottky catalyst for OER and MOR. O−CNT acts as a co‐catalyst which effectively regulates the charge transfer in Ni−Fe2 O3 and thus enhances the electrocatalytic performance. Ni−Fe2 O3 /O−CNT exhibits a low onset potential of 260 mV and overpotential 310 mV @ 10 mA cm −2 for oxygen evolution. Being a Mott‐Schottky catalyst, it achieves the higher flat band potential of −1.15 V with the carrier density of 0.173×10 24 cm −3 . Further, in presence of 1 M CH3 OH, it delivers the MOR current density of 10 mA cm −2 at 1.46 V vs. RHE. The excellent electrocatalytic OER and MOR activity of Ni−Fe2 O3 /O−CNT could be attributed to the synergistic interaction between Ni‐doped Fe2 O3 and O−CNT. Abstract : A hybrid of Nickel doped hematite (Ni−Fe2 O3 ) nanosheets and surface oxidized multiwalled carbon nanotubes (O−CNTs) has been prepared using wet chemistry techniques which we labeled as Ni−Fe2 O3 /O−CNTs. Interestingly, Ni−Fe2 O3 /O−CNTs composite demonstrates both the electrochemical water and methanol oxidation activity, OER and MOR respectively. In the resulting composite, O−CNTs performs as a co‐catalyst and offers tremendous conductive networks to promote the charge transfer within Ni−Fe2 O3, which eventually boosts the electrocatalytic oxidation process.