Synergistic Effect of Cr³⁺ on Layered Double Hydroxide Supported Cu⁰ Nanoparticles for the Oxidation of Alcohols and Hydrocarbons

Abstract

Chromium(III)‐doped layered double hydroxide supported copper nanoparticles (Cr3+‐Cu0/LDH) has been prepared as an efficient and reusable catalyst using simple and versatile synthetic method. Effect of doping of Cr3+ to the layered double hydroxide supported Cu0 nanoparticles was evaluated for the oxidation of alcohols and hydrocarbons by varying the amount of Cr3+ loading in the catalyst. The catalyst with Cu:Cr ratio= 1:1 afforded highest catalytic activity among the synthesized catalysts towards the oxidation using TBHP (tBuOOH) in aqueous medium and was structurally characterized by Fourier Transform Infrared Spectroscopy (FTIR), X‐Ray Diffraction Spectroscopy (XRD), Field Emission Gun‐Scanning Electron Microscopy (FEG‐SEM), Energy‐dispersive X‐Ray Spectroscopy (EDX), High Resolution‐Transmission Electron Spectroscopy (HR‐TEM), Inductively Coupled Plasma Atomic Emission Spectroscopy (ICP‐AES) and X‐Ray Photoelectron Spectroscopy (XPS). The high activity and selectivity was assigned to the synergistic electronic interaction between copper(0) nanoparticles and chromium(III) ions based on experimental data and XPS results. Moreover, the high stability of Cu0 and Cr3+ in the catalyst was attributed to the strong metal‐support interactions, which make the catalyst recyclable upto five runs.

Fabrication and Characterization of Cu Nanoparticles Dispersed on ZnAl-Layered Double Hydroxide Nanocatalysts for the Oxidation of Cyclohexane

“…The surface also had some imperfections, indicating that it had a high adsorption capacity. The SEM images also showed that the crystallinity of the nanocatalyst corresponded to the XRD pattern’s characteristic reflections Figure e,f shows the chemical composition of the nanocatalyst as determined by EDX analysis.…”

“…The SEM images also showed that the crystallinity of the nanocatalyst corresponded to the XRD pattern’s characteristic reflections. 24 Figure 2 e,f shows the chemical composition of the nanocatalyst as determined by EDX analysis. The nanocatalyst, CuNPs@LDH, contains carbon, oxygen, zinc, aluminum, and copper metals, indicating that a heterogeneous nanocatalyst has successfully synthesized.…”

“…Particle size plays a key role in catalytic reactions because the catalytic reaction takes place on the metal surface of the catalyst, and it is reasonable to assume that smaller metal particles have more surface area and hence more activity. The immobilization of nanoparticles on the surface of insoluble inorganic supports has attracted a lot of interest. − However, to the best of our knowledge, the investigation of Cu nanoparticles supported on layered double hydroxide as a nanocatalyst for the oxidation of cyclohexane is rarely reported.…”

“…The immobilization of nanoparticles on the surface of insoluble inorganic supports has attracted a lot of interest. 20 − 24 However, to the best of our knowledge, the investigation of Cu nanoparticles supported on layered double hydroxide as a nanocatalyst for the oxidation of cyclohexane is rarely reported.…”

Imidazolized Activated Carbon Anchoring Phosphotungstic Acid as a Recyclable Catalyst for Oxidation of Alcohols With Aqueous Hydrogen Peroxide

“…Ten years ago, ruthenium hydroxide supported on silica was used as an efficient catalyst for the aerobic oxidation of monoterpene alcohols ( Costa et al, 2011 ). Recently, layered double hydroxide-supported Cu 0 nanoparticles ( Choudhary et al, 2019 ), Au nanoparticles ( Karimi et al, 2020 ), and polymeric ionic liquid microspheres/Pd nanoparticles ( Wu et al, 2020 ) have been designed for the oxidation of alcohols. It was presented that primary and secondary alcohols can be efficiently oxidized using CoFe 2 O 4 @HT@Imine-Cu II and TEMPO in the air atmosphere ( Salimi et al, 2020 ).…”