Synthesis and application of biogenic gold nanomaterials with 1 0 0 facets for crude glycerol electro-oxidation
By Velázquez-Hernández, Isaac; Estévez, Miriam; Vergara-Castañeda, Hayde; Guerra-Balcázar, Minerva; Álvarez-Contreras, Lorena; Luna-Bárcenas, Gabriel; Pérez, Claudia; Arjona, Noé; Pool, Héctor
Published in Fuel
2020
Abstract
In this work, gold nanomaterials were obtained using aqueous extracts of black carrots varying the molar ratio between the extract and the gold precursor salt (1:10, 1:5 and 2:5). Additionally, Au nanoparticles were obtained by the Turkevich method as reference material (Au Turkevich). Transmission electron micrographs indicated that a 1:5 ratio allowed to obtain a mixture of gold shapes like triangular, plate, rod, wire, and hemispherical shapes. The electrocatalytic evaluation for 0.5 M glycerol electro-oxidation indicated that Au (1:5) displayed higher current density (298.26 vs. 230.25 mA mg−1), and a more negative onset potential (ΔE = 150 mV) than Au Turkevich. In addition, Au (1:5) displayed higher current density during the electro-oxidation of 1 M crude glycerol (466.91 vs. 244.73 mA mg−1) with a similar potential difference. The improvement in activity and durability presented by Au (1:5) was attributed to the abundance of 1 0 0 facets as was determined by X-ray diffraction and HR-TEM.