NiCo ₂ O ₄ ‐rGO /Pt as a robust nanocatalyst for sorbitol electrooxidation

Abstract

A ternary nanocatalyst consisting of nickel cobalt oxide (NiCo 2 O 4 ), reduced graphene oxide (rGO), and platinum (Pt) was introduced as a promising catalyst for application in the sorbitol oxidation reaction (SOR) process for use in fuel cells. Other catalysts such as NiCo 2 O 4 , NiCo 2 O 4 -rGO, and NiCo 2 O 4 /Pt were prepared for comparison. The structure and morphology of the synthesized nanocatalysts were examined by X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The efficiency of the as-synthesized materials was assessed by electrochemical tests of cyclic voltammetry (CV), linear sweep voltammetry (LSV), electrochemical impedance spectroscopy (EIS), and chronoamperometry (CA). The comparison of the SOR process for the synthesized nanocatalysts showed that NiCo 2 O 4 -rGO/Pt has the highest current density (57.2 mA cm À2 , 45.04 mA/mg) at a scan rate of 10 mV/s and the lowest peak potential (0.64 V) as well as the highest cyclic stability than other materials. The superior electrocatalytic performance is attributed to the synergistic effect of the components. Moreover, the charge transfer resistance of SOR for NiCo 2 O 4 -rGO/Pt catalyst is 702 Ω, lower than that for NiCo 2 O 4 /Pt (930 Ω). Thus, NiCo 2 O 4 -rGO/Pt constitutes an efficient and promising nanocatalyst for SOR.

Energy intensity among European Union countries: the role of renewable energy, income and trade

“…It is this feature that makes renewable energy from sources including solar, ocean, hydro and plant materials very crucial for reducing carbon dioxide emission (Salarizadeh et al, 2022). It also guarantees reliable energy supply than fossil fuel (Askari et al, 2022). Regarding trade openness, it has been documented that its effect on energy intensity is inconclusive as it can increase or reduce energy intensity depending on whether it facilitates or inhibits efficiency (Adom, 2015a(Adom, , 2015b(Adom, , 2015c.…”

Fabrication of Mn3O4-CeO2-rGO as Nanocatalyst for Electro-Oxidation of Methanol

“…For Mn 3 O 4 -CeO 2 -rGO, it was also observed that the anodic peak current density increased up to a scan rate of 90 mV/s, and after that, the current density decreased. It is likely that at higher scan rates, the electrolyte and methanol do not have enough time to fully engage with the catalyst and penetrate to its core, reducing current density [ 49 ]. The current density for Mn 3 O 4 -CeO 2 at scan rates of 10, 70, and 110 mV/s were 5.9, 8.8, and 7.9 mA/cm 2 , respectively, and for Mn 3 O 4 -CeO 2 -rGO at scan rates of 10, 90, and 110 mV/s were 11.6, 17.7, and 16.05 mA/cm 2 (the selected scan rates are the lowest, optimal, and the maximum scan rates, respectively).…”

NiO–Co3O4–rGO as a Multicomponent Transition Metal Oxide Nanocatalyst for Ultra‐level Detection of Nitrite in Beef and Tap Water Samples

“…Carbon materials, especially reduced graphene oxide (rGO), have excellent electrical conductivity which can improve the metal oxide properties. [ 31 ] Moreover, due to high surface area, rGO can be an attractive choice for promoting the electrocatalytic effects of metal oxide composites. [ 32,33 ]…”

“…[30] Carbon materials, especially reduced graphene oxide (rGO), have excellent electrical conductivity which can improve the metal oxide properties. [31] Moreover, due to high surface area, rGO can be an attractive choice for promoting the electrocatalytic effects of metal oxide composites. [32,33] In this study, NiO-Co 3 O 4 (NC) and NiO-Co 3 O 4 -rGO (NCR), as two metal component nanocatalysts, were synthesized by a hydrothermal method and the structure of the nanomaterials was characterized by complementary techniques.…”