Microwave-Assisted Synthesis of CuO Nanoparticles Using Cordia africana Lam. Leaf Extract for 4-Nitrophenol Reduction

Abstract

Copper-oxide-based nanomaterials play an important role as a low-cost alternative to nanoparticles of precious metals for the catalytic reduction of 4-nitrophenols. In this study, CuO nanoparticles were synthesized by a microwave-assisted method using Cordia africana Lam. leaf extract for reduction or stabilization processes. The synthesized CuO nanoparticles (NPs) were characterized using X-ray diffraction analysis (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and energy-dispersive spectroscopy (EDS). The analysis indicated that nanocrystals of the monoclinic CuO phase having a cluster of agglomerated morphology with a crystallite size of about 9 nm were synthesized. We also evaluated the catalytic performance of CuO NPs against 4-nitrophenol (4-NP) reduction. The catalyst has shown excellent performance completing the reaction within 12 min. Furthermore, the performance of CuO NPs synthesized at different pH values was investigated, and results indicated that the one synthesized at pH 7 reduced 4-NP effectively in shorter minutes compared to those obtained at higher pH values. The CuO NPs synthesized using Cordia africana Lam. leaf extract exhibited a better reducing capacity with an activity parameter constant of 75.8 min−1·g−1. Thus, CuO synthesized using Cordia africana Lam. holds a potential application for the catalytic conversion of nitroarene compounds into aminoarene.

Waste Biomass-Derived Activated Carbon-Supported 0D, 1D, 2D, and 3D Nanostructures of Copper Oxide for Hydrogenation Reaction: A Study on the Role of Structural Properties

“…After investigating the development of the optimized conditions for hydrogenation reactions, these conditions were assessed to substrate scope screening over the different shapes CuO supported activated carbon toward hydrogenation reactions of the selected substrate of 10 different nitro compounds were tested and these results, times were summarized in Figure (entry 1a–j). Moradi et al used strong reducing agents like NaBH 4 but our work used a mild base like KOH, and a green solvent, ethanol, was used. , The highly selective catalyst of CuO/FGNC nanocomposites enhances the selectivity in the hydrogenation reactions, whereas the nitro group only reduces in the presence of different functional groups such as halide, phenol, and methyl groups. , Finally, we obtained the desired product. All of the examined aromatic nitro derivatives exhibit high TON and TOF was found.…”

“…In recent years, many protocols have used precious metals like Pd, Pt, Rd, and Ru, but the noble metals are moisture sensitive, nonreusable, and have limited availability. It is still necessary to develop a new procedure that might induce a potentially high reduction of nitro compounds into amines using low-cost metals like Fe, Ni, Cu, Co, and so on. ,, A lot of protocols are already applicable in the field of nitro reduction. However, there are some limitations, such as selectivity problems, so environmentally unhealthy impurities or byproducts were obtained.…”

Enhancement of catalytic reduction of 4-nitrophenol using MoO3 nanobelts incorporated SiO2 nanocomposite fabricated by nanosecond pulsed laser ablation technique

“…The value is about 59 times and 4.5 times higher than those of SnO 2 NFs (7.1 × 10 -5 S -1 ) and MoS 2 NSs (9.2 × 10 -4 S -1 ), respectively [31]. Classical reduction catalysts are made from mostly toxic and expensive noble metals such as Au, Pt, Pd, and Ru [32][33][34][35]. On the other hand, MoO 3 has attracted progressive attention as an alternative to the noble metals catalysts perhaps due to its low cost, nontoxicity, and the existence of multiple oxidation states.…”

Influence of band gap and carrier concentration on ZnO/CuO solar cells performance

“…The combination of nanomaterials particularly metal oxides as n-type and p-type are outstanding key for fabrication of photonic devices involving solar cells and light emitting diodes (LEDs) [1,2] . Among such oxides, copper oxide (CuO) is promising candidate as it has unique properties like stability, high absorption coefficient in the region of visible light [3] , CuO is a p-type direct bandgap semiconductor with energy of about 1.4 eV [4] .…”