Metal Oxide (Co3O4 and Mn3O4) Impregnation into S, N-doped Graphene for Oxygen Reduction Reaction (ORR)

Abstract

To address aggravating environmental and energy problems, active, efficient, low-cost, and robust electrocatalysts (ECs) are actively pursued as substitutes for the current noble metal ECs. Therefore, in this study, we report the preparation of graphene flakes (GF) doped with S and N using 2-5-dimercapto-1,3,4-thiadiazole (S3N2) as precursor followed by the immobilization of cobalt spinel oxide (Co3O4) or manganese spinel oxide (Mn3O4) nanoparticles through a one-step co-precipitation procedure (Co/S3N2–GF and Mn/S3N2–GF). Characterization by different physicochemical techniques (Fourier Transform Infrared (FTIR), Raman spectroscopy, Transmission Electron Microscopy (TEM) and X-ray Diffraction (XRD)) of both composites shows the preservation of the metal oxide spinel structure and further confirms the successful preparation of the envisaged electrocatalysts. Co/S3N2–GF composite exhibits the best ORR performance with an onset potential of 0.91 V vs. RHE, a diffusion-limiting current density of −4.50 mA cm−2 and selectivity for the direct four-electron pathway, matching the results obtained for commercial Pt/C. Moreover, both Co/S3N2–GF and Mn/S3N2–GF showed excellent tolerance to methanol poisoning and good stability.

Transition metal oxides with perovskite and spinel structures for electrochemical energy production applications

“…Carbon materials are excellent candidates to fulfil this role taking into account their interesting properties such as high electrical conductivity, high thermal stability, high surface area, and, in some cases, low price. Different types of carbon materials have been used for this purpose, such as carbon blacks (De Koninck et al, 2007;Kéranguéven et al, 2015), carbon nanotubes (Alexander et al, 2018;Zhang et al, 2020e;Li et al, 2019), graphene-based materials (Hu et al, 2015;Samanta and Raj, 2019;Rebekah et al, 2020;Zhuang et al, 2021), activated carbons (Hu et al, 2018;Flores-Lasluisa et al, 2019b) and nitrogen-doped carbon materials (Chen et al, 2017;Park et al, 2015;Najam et al, 2020;Wu et al, 2018b;Mathumba et al, 2020;Liu et al, 2021). Nevertheless, no sufficient attention is paid to the effect of the structure (at different levels) and surface chemistry of the carbon material on the interaction with the metal oxide and on its role on the catalytic activity improvement.…”

Preparation of Octahedral Mn3O4 by Liquid Phase Method

“…The traditional cathode material of lithium manganate (LiMn 2 O 4 ) battery was mainly prepared by high temperature solid state method with MnO 2 as manganese source. The battery material prepared by this method had low capacity, poor high-temperature performance and poor economic benefits, which could not meet the demand of lithium battery industry for high-quality manganese oxide [5][6][7]. In recent years, octahedral manganese trioxide had been widely used in lithium battery industry [8].…”

Nanocomposites Prepared from Carbon Nanotubes and the Transition Metal Dichalcogenides WS2 and MoS2 via Surfactant-Assisted Dispersions as Electrocatalysts for Oxygen Reactions

“…In this context, carbon-based nanomaterials emerged as potential alternatives to Ptbased electrocatalysts, and, therefore, have been increasingly investigated. Carbon quantum-dots (CQDs) [6,7], N-doped carbon nanotubes [8,9] and N-doped graphene [10,11] have been reported to have good electrocatalytic behavior towards ORR. Graphene quantum dots, either heteroatom-doped [12] or decorated with non-Pt metals [13,14], have also been described as good ORR electrocatalysts.…”