Cation exchange synthesis of Ni_xCo_(3−x)O₄(x= 1.25) nanoparticles on aminated carbon nanotubes with high catalytic bifunctionality for the oxygen reduction/evolution reaction toward efficient Zn–air batteries

Abstract

NixCo(3–x)O4/NH2-CNTs for ORR and OER is successfully synthesized by a cation exchange reaction.

Cation/Anion Exchange Reactions toward the Syntheses of Upgraded Nanostructures: Principles and Applications

“…164 With regard to increasing the specific surface area, many studies have focused on the syntheses of hollow metal sulfide NCs via AER between metal oxides and sulfur precursor, such as Co 4 S 3 by Co 3 O 4 , 16 NiS by NiO, 165 nanoparticles on an aminated carbon nanotube exhibited bifunctionality for oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) properties. 168 The amorphous Ni-Co bimetallic hydroxide prepared via CER exhibited enhanced performances for hybrid supercapacitor applications. 169 Based on CER-enabled composition and phase tailoring, Lee and colleagues reported the synthesis of highly crystalline Pd 13 Cu 3 S 7 nanoplates by partial CER of Cu 1.81 S nanoplates, which exhibited enhanced activity for an electrocatalytic hydrogen evolution reaction (HER), compared with Cu 1.81 S templates and amorphous PdCuS nanoplates.…”

FeCo Alloy Nanoparticles Coated by an Ultrathin N-Doped Carbon Layer and Encapsulated in Carbon Nanotubes as a Highly Efficient Bifunctional Air Electrode for Rechargeable Zn-Air Batteries

“…Direct electrochemical conversion between oxygen and water has attracted great attention, due to its vital role in fuel cells (FCs) and metal-air batteries (MABs). − Especially, oxygen reduction (ORR) and evolution (OER) reactions are paramount electrochemical processes, whose sluggish kinetics and large overpotentials have been considered as the main bottlenecks hindering the commercial applications of MABs and FCs in real-world devices. − Presently, precious-metal-based catalysts, such as platinum (Pt) and its alloys, are state-of-the-art catalysts for ORR, but they exhibit low OER activities. Iridium (Ir) and ruthenium (Ru) oxide-based catalysts have extraordinary OER activities, but they possess low ORR activities. ,, These catalysts are also confronted with the problems of high cost, scarcity, and poor stability, greatly limiting the comprehensive applications of these precious-metal-based catalysts in ORR and OER. ,, To improve the performance of MABs and FCs and promote their widespread uses, it is necessary to develop efficient and inexpensive bifunctional electrocatalysts for both ORR and OER, although it remains a huge challenge since the catalysts efficient for ORR are often unfavorable to OER and vice versa .…”

Rational Design for the Synthesis of Europium Vanadate-Encapsulated Graphene Oxide Nanocomposite: An Excellent and Efficient Catalyst for the Electrochemical Detection of Clioquinol

“…11−15 Especially, graphene oxide (GO) is a promising electrode material for electrochemical sensors because of its oxygen-rich functional groups such as epoxides, carbonyls, hydroxides, and more reactive sites for covalent functionalization. 11,12 As is denoted mainly in scientific literature over the past few years, GO yields distinguished chemical stability, good water dispersibility, high specific surface area, remarkable electronic property, excellent biocompatibility, and strong conductivity. 13 Particularly, the GO has π−π electrostatic stacking properties and fast electrontransfer kinetics; it is a strong candidate as excellent electrode material.…”

“…Furthermore, various carbon derivatives have been reported as potential electrode materials for electrochemical sensing applications. − Especially, graphene oxide (GO) is a promising electrode material for electrochemical sensors because of its oxygen-rich functional groups such as epoxides, carbonyls, hydroxides, and more reactive sites for covalent functionalization. , As is denoted mainly in scientific literature over the past few years, GO yields distinguished chemical stability, good water dispersibility, high specific surface area, remarkable electronic property, excellent biocompatibility, and strong conductivity . Particularly, the GO has π–π electrostatic stacking properties and fast electron-transfer kinetics; it is a strong candidate as excellent electrode material. − Importantly, the GO suspension in aqueous or low ionic strength buffers can be more stable at room temperature for some years without any other additional surfactants. − Therefore, incorporating EuV with GO will not only improve the excellent electron conductivity and sensitivity of the nanocomposite but also introduce heterojunctions, more surface defects, catalytic properties, grain boundaries, surface-to-volume ratio, and superior electronic properties to improve the sensing performance.…”