ABSTRACT Green synthesis is an alternative route for obtaining nanomaterials, avoiding the use of toxic reagents. In this work, ZnO nanoparticles were synthesized using Eucalyptus communis and Larrea tridentata plant extracts as reducing and stabilizing agents. The phytochemical composition of each extract strongly affected the morphological properties of the ZnO. FTIR and Raman spectroscopy confirmed the participation of polyphenols, flavonoids, and lignans in nanoparticle formation, while XRD Rietveld refinement showed that both routes yielded hexagonal wurtzite ZnO with crystallite sizes of ∼40 nm. SEM analysis revealed quasi‐spherical agglomerates for ZnO–Eucalyptus and more faceted, crystalline morphologies for ZnO–Larrea, in agreement with particle‐size analysis showing broader distributions for the latter. Both nanomaterials were tested in methylene blue dye photodegradation under solar irradiation. ZnO‐Larrea showed markedly superior performance, achieving almost complete dye degradation within 45 min, whereas ZnO‐Eucalyptus required 120 min to reach the same extent of removal. The enhanced activity of ZnO–Larrea was attributed to the presence of graphitized surface residues that improve dye adsorption and photon absorption, promoting more efficient charge separation and reactive‐species generation. These results demonstrate that plant‐mediated synthesis using Larrea tridentata and Eucalyptus extracts yields robust ZnO nanoparticles with high photocatalytic potential, providing a sustainable strategy for pollutant removal.
Martínez‐Castillo et al. (Sun,) studied this question.