Nanocomposite Synthesis from a Natural Clay-Rich Soils and Exhausted Coffee Grounds for Environmental Applications

• Published in: Journal of nano research Vol. 63; pp. 47 - 63
• Main Authors: Fernández-Luqueño, Fabián, Sánchez-Castro, María Esther, Roa-Velázquez, Daniela, Rodríguez-Varela, Francisco Javier, Torres-Huerta, Aidé Minerva, Urdapilleta-Inchaurregui, Vianey
• Format: Journal Article
• Language: English
• Published: Zurich Trans Tech Publications Ltd 10.06.2020
• Subjects: Antiinfectives and antibacterials; Antimicrobial agents; Catalytic activity; Clay soils; Coffee; Crystal structure; Crystallinity; Energy gap; Liquid nitrogen; Methylene blue; Nanocomposites; Nanomaterials; Nanoparticles; Organic compounds; Oxidation; Photocatalysis; Photoelectrons; Pollutants; Silver; Soil pollution; Soil porosity; Soil water; Spectrum analysis; Surface properties; Titanium dioxide; Ultraviolet reflection; Antimicrobial; Photodegradation; Photocatalytic; Environmental Pollution; Natural Soil; Nanoremediation; Remediation; Surface Area; Water Treatment
• ISSN: 1662-5250; 1661-9897; 1661-9897
• DOI: 10.4028/www.scientific.net/JNanoR.63.47

Natural clays, engineered Ag-nanoparticles (NP), TiO2-NP, and exhausted coffee grounds were used to synthesize a nanocomposite 7NC using a Vertisol soil through a single-step by thermal method, to build a nanomaterial to degrade or filtrate pollutants from soils, water or air. The surface characteristics and the porosity of the composite were studied through nitrogen gas adsorption at liquid nitrogen temperature and application of the Brunauer–Emmett–Teller (BET) equation and the results indicated that the microporous composites ranged a surface area of 17.36 m2 g-1. X-ray diffraction showed crystalline structure and crystalline phase of the nanocomposites. HR-TEM-STEM results demonstrated that TiO2-NP surrounded Ag-NP, and both were impregnated on natural soil nanoparticles. Oxidation states of the Ag-NP and TiO2-NP were analyzed by X-ray photoelectron spectroscopy (XPS) The energy gap of nanocomposite 7NC was determined using the Kubelka-Munck model from Ultraviolet–visible diffuse reflectance (UV–Visible DRS) spectra. The photocatalytic activity of these nanocomposites was evaluated, and the results indicated that nanocomposite with Vertisol-soil-NP (7NC) degraded the harmful organic compound methylene blue (MB) while the antimicrobial activity and resistance against Escherichia coli and Staphylococcus aureus and the zone of inhibition (ZOI) also were analyzed. The nanocomposites Ag-NP/TiO2-NP/natural-soil-NP/exhausted coffee-ground showed its for the development of an efficient material for environmental remediation with photocatalytic and antimicrobial activity.