Research Outputs
In situ synthesis of Cu2O nanoparticles using eucalyptus globulus extract to remove a dye via advanced oxidation
Water pollution, particularly from organic contaminants like dyes, is a pressing issue, prompting exploration into advanced oxidation processes (AOPs) as potential solutions. This study focuses on synthesizing Cu2O on cellulose-based fabric using Eucalyptus globulus leaf extracts. The resulting catalysts effectively degraded methylene blue through photocatalysis under LED visible light and heterogeneous Fenton-like reactions with H2O2, demonstrating reusability. Mechanistic insights were gained through analyses of the extracts before and after Cu2O synthesis, revealing the role of phenolic compounds and reducing sugars in nanoparticle formation. Cu2O nanoparticles on cellulose-based fabric were characterized in terms of their morphology, structure, and bandgap via SEM-EDS, XRD, Raman, FTIR, UV–Vis DRS, and TGA. The degradation of methylene blue was pH-dependent; photocatalysis was more efficient at neutral pH due to hydroxyl and superoxide radical production, while Fenton-like reactions showed greater efficiency at acidic pH, primarily generating hydroxyl radicals. Cu2O used in Fenton-like reactions exhibited lower reusability compared to photocatalysis, suggesting deterioration. This research not only advances understanding of catalytic processes but also holds promise for sustainable water treatment solutions, contributing to environmental protection and resource conservation.
Green synthesis of Ag/Ag2O nanoparticles on cellulose paper and cotton fabric using Eucalyptus globulus leaf extracts: Toward the clarification of formation mechanism
The present study reports on phenolic compounds profile of Eucalyptus globulus leaf extracts and exhibiting their role in obtaining silver nanoparticles (AgNP) by a green method on paper and fabric supports with or without addition of NaOH. To know the mechanism involved in the formation of AgNP, FTIR, UV–Visible spectrophotometry and UHPLC-QTOF-MS analyzes were carried out of E. globulus extracts before and after the synthesis of AgNP. The FTIR, UV–Visible spectrophotometry analyzes identified phenolic compounds, and to a lesser extent reducing sugars mainly participate as reducing agents in the formation of AgNP, while phenolic compounds would participate as stabilizing agents. UHPLC-QTOF-MS analyzes identified derived from gallic acid play an important role in AgNP formation. AgNPs were characterized in their morphology and structure by SEM-EDS, TEM-SAED, XRD, UV–Vis diffuse reflectance and TGA. The results indicate the formation of Ag and/or Ag2O nanoparticles depending on the influence of NaOH in the reaction system. Furthermore, the support used (paper or fabric), it would influence the concentration of AgNPs formed, the consumption of phenolic compounds, the antibacterial activity and band-gap of AgNPs synthesized. This study provides evidence of a simple process to support AgNP on cellulose and providing key information towards the definitive clarification of the mechanism of formation of AgNP by green synthesis.