Waste Eggshell-Derived Dual-Functional CuO/ZnO/Eggshell Nanocomposites: (Photo)catalytic Reduction and Bacterial Inactivation

Abstract

Transforming biological waste into high value-added materials is of significant importance to environmental protection and sustainable development of economy. Eggshell as a type of naturally occurring organic–inorganic biomaterials featuring a unique hierarchically porous structure has been widely investigated in the fields of catalysis and adsorption, as well as energy. Herein, CuO/ZnO/eggshell (CZ/ES) composites were rationally fabricated by using waste eggshell as a template. After a simple deposition and calcination process, the CuO and ZnO nanoparticles were evenly distributed over the surface of the CaCO3. The (photo)­catalytic activity and antibacterial properties of the nanocomposites were subsequently investigated. The results showed that the CZ/ES nanocomposite exhibited a superior catalytic reduction and antibacterial activity. The catalytic reduction reaction rate constant K app of 4-nitrophenol under the irradiation of UV–vis light was calculated to be approximately five times higher than that obtained in the absence of light irradiation. Besides, the CZ/ES nanocomposite exhibited significant antibacterial property for the destruction of E. coli and S. aureus. The enhanced performance in the (photo)­catalytic reduction of 4-nitrophenol and bacterial disinfection of CZ/ES may be attributed to the strong reactant absorbance capacity, large amounts of reaction sites, and improved separation efficiency of the electrons. Furthermore, the reaction mechanism of the catalytic reduction of 4-nitrophenol was also discussed in detail.

<p>Bio Framework-Derived Facile MoO3-NiO-PdO-Pd Nanomaterial for Detoxification of Organic Pollutants</p>

“…20 In previous studies such organic groups were achieved by graphene oxides, multiwalled carbon nanotubes, etc. 20,21,22 However, in the current study such groups were incorporated into metal oxide nanoparticles by economic, and efficient synthesizing fuel, which was procured from Abies pindrow Royle foliage. The foliar fuel based synthesis of nanomaterials is widely investigated and reported.…”

State-of-the-Art of Eggshell Waste in Materials Science: Recent Advances in Catalysis, Pharmaceutical Applications, and Mechanochemistry

“…Remarkably, the aforementioned pollutant could be completely degraded by using CuO/ZnO/eggshell sample, within 8 min under light irradiation, most likely due to the efficient charge separation and the good absorbance features. Moreover, the catalyst exhibited a good stability over 5 reaction cycles, demonstrating to be a sustainable and effective candidate for photocatalytic degradation of pollutants (Zhang et al, 2019a ) ( Figure 3C ). Besides their application for 4-NP reduction, similar materials have been also used for the photocatalytic degradation of methyl orange, achieving excellent results (He et al, 2019 ).…”

“…Reprinted from Zhang et al ( 2020a ), Copyright (2020), with permission from Elsevier; (C) Schematic representation of 4-NP degradation using CuO/ZnO/eggshell. Reprinted by permission from Springer Nature Customer Service Centre GmbH: Springer Nature (Zhang et al, 2019a ), Copyright (2019).…”

Preparation, characterization and photocatalytic performance of heterostructured CuO–ZnO-loaded composite nanofiber membranes

“…Recently, researches on the application of CuO-ZnO nanocomposites in the photocatalytic degradation of organic pollutants were performed [46][47][48]. In this study, the photocatalytic degradation experiments under UV irradiation were carried out using the four prepared CNFMs in order to degrade a methyl orange solution with a concentration of 10 mg/L.…”