Green Synthesis of Flower-Shaped Copper Oxide and Nickel Oxide Nanoparticles via Capparis decidua Leaf Extract for Synergic Adsorption-Photocatalytic Degradation of Pesticides

Abstract

Green manufacturing of catalysts enables sustainable advanced oxidation processes and water treatment processes for removing trace contaminants such as pesticides. An environmentally friendly biosynthesis process produced high-surface-area CuO and NiO nanocatalysts using phytochemicals in the Capparis decidua leaf extract, which served as a reductant and influenced catalyst shape. Capparis decidua is a bushy shrub, widely distributed in dry and arid regions of Africa, Pakistan, India, Egypt, Jordan, Sudan, Saudi Arabia. The synthesized CuO and NiO nanoparticles were characterized by UV-vis spectroscopy (UV-vis), field emission scanning electron microscopy (FESEM), energy-dispersive X-ray spectroscopy (EDS), Fourier transform infrared spectroscopy (FT-IR), and X-ray diffraction (XRD) and thermo-gravimetric analysis/differential thermal analysis (TGA/DTA). The produced nanoparticles were spherical and flower-like in shape and have a characteristic face-centered cubic structure of CuO and NiO. Biosynthesized catalysts were photoactive and degraded recalcitrant pesticide Lambda-cyhalothrin (L-CHT). Photocatalytic degradation of L-CHT was affected by the initial L-CHT concentration, solution pH levels between 5 and 9, and photocatalyst concentration. The L-CHT removal percentage attained by CuO photocatalyst (~99%) was higher than for NiO photocatalyst (~89%). The degradation of L-CHT follows a pseudo-first-order kinetic model, and the apparent rate constant (kapp) decreased from 0.033 min−1 for CuO to 0.0084 min−1 for NiO photocatalyst. The novel flower-shaped nanoparticles demonstrated high stability in water and recyclability for removing L-CHT pesticide contamination in water.

Metal Oxides Nanoparticles: General Structural Description, Chemical, Physical, and Biological Synthesis Methods, Role in Pesticides and Heavy Metal Removal through Wastewater Treatment

“…Another study reported by Iqbal et al [ 168 ] showed a simple, ecofriendly, and stable synthesis of CuO and NiO nanoparticles using Capparis decidua leaf extract. The fabricated nanoparticles were analyzed using different techniques, including UV-vis, FE-SEM, XRD, and FT-IR.…”

“…The reusability of CuO and NiO NPs against L-CHT was tested and can be for up to five runs. The results indicate the potential usage of CuO and NiO NPs photocatalysts for water treatment and the removal of pesticides [ 168 ].…”

Aloe Vera Extract-Mediated CuO NPs as Catalysts for the Synthesis of 4-Hydroxy-3-Methoxybenzaldehyde-Connected Piperidine Derivatives and Their Antibacterial Activity

“…Figure 4 shows the steps for making CuO NPs with aloe vera extract. Te above-given procedure was followed by previously reported method [55].…”

The Surge of Metal–Organic-Framework (MOFs)-Based Electrodes as Key Elements in Electrochemically Driven Processes for the Environment

“…Furthermore, both species can generate reactive oxygen species in an aqueous solution such as superoxide (O2 − ) from dissolved oxygen reduction by Reaction ( 7) and hydroxyl radical from water oxidation by Reaction ( 8) [90]. The high reactivity of both charge carriers can be exploited in redox chemistry applied to the environment, such as water splitting by Reaction ( 9) [91,92], organic pollutants (R) oxidation according to general expression (10) [93,94], metal pollutants (M) reduction by Reaction (11) [95,96], CO2 reduction following Reactions ( 12)-( 14) [97,98], etc. A schematic of the photoelectrocatalytic degradation process can be found in Figure 11.…”