Green synthesis of bimetallic Pt@Cu nanostructures for catalytic oxidative desulfurization of model oil

Abstract

This study reports the synthesis of bimetallic Pt@Cu nanostructures at elevated temperature of 100°C using Alchornea laxiflora leaf extract (ALLE). The nanostructures have been characterized using UV-vis spectroscopy, high resolution transmission electron microscopy (HRTEM), Fourier Transform Infrared spectroscopy (FTIR), energy dispersive X-ray(EDX) spectroscopy and X-ray diffraction (XRD) techniques. The sizes of the bimetallic Pt@Cu nanostructures range from 1.87 to 2.38 nm with an average particle size of 2.12 ± 0.21 nm, and they crystallized in face-centered cubic (fcc) symmetry. The EDX analysis confirms the bimetallism of Pt@Cu nanostructures and individual metals are present in the ratio 2:3. FTIR indicates strong peaks at 3427 cm -1 which is attributed to hydroxyl group of polyphenolic compounds in ALLE, and the peak disappeared completely in the FTIR of Pt@Cu nanostructures, thus confirming their significant roles in bioreduction process. Catalytic oxidative property of Pt@Cu nanostructures was investigated by oxidation of a model oil [dibenzothiophene (DBT) dissolved in n-heptane] to their corresponding sulfone. Our results show that bimetallic Pt@Cu nanostructures have higher catalytic oxidative activity than the conventional acetic acid that is used in the oxidative desulfurization process. The catalytic oxidative desulfurization activity shown by the Pt@Cu nanostructures promises the potential application in petroleum industry.

A current overview of the oxidative desulfurization of fuels utilizing heat and solar light: from materials design to catalysis for clean energy

“…In the field of catalysis, metal oxides with a Lewis acid characteristic are prominent and inveterate catalysts that speed up most important reactions, such as oxidation and acid-base reactions, compensating for the drawback of poor selectivity. 58,59 Significantly, metal oxides have been advocated to replace precious metals such as Pt 60 and Au 61 in performing ODS to counter the high price and restricted availability that are stumbling blocks to their industrial application. In line with previous research, various relatively economical metal oxides, such as MoO 3 , WO 3 , Co 3 O 4 , MnO 2 and so on, have been highlighted as promising candidates for fuel purification via ODS.…”

Engineering Highly Dispersed Pt Species by Defects for Boosting the Reactive Desulfurization Performance

“…However, after coupling with Pt, the catalytic activity was significantly improved and the DBT conversion reached 91.5% in 4 h. Herein, the turnover frequency (TOF) value is 69.5 (per mol of Pt, h –1 ), which is much higher than other Pt-based catalysts (Table ). ,, This may be due to the fact that defective tungsten oxide stabilizes and disperses Pt species, which leads to the electron interaction between the metal and the support. Therefore, when the catalyst has a low Pt loading, the reaction still maintains a high catalytic oxidation performance.…”

Synthesis, Properties, and Biological Applications of Metallic Alloy Nanoparticles

“…Monometallic nanoparticles as well as metallic alloy nanoparticles have been manufactured using plant-based approaches. For instance, Ag–Ni, Ag–Co, Pt–Cu, Au–Ag, Ag–Cu, and Zn–Ag nanoparticles have been produced using the leaf extracts of Canna indica , Alchornealaxiflora , Azadirachta indica, Cacumen Platycladi , palm, Mirabilis jalapa, and Moringa oleifera [ 179 , 180 , 181 , 182 , 183 , 184 , 185 ], Au–Ag–Sr, and Fe–Ag–Pt nanoparticles were produced from the roots of coriander, Platycodon grandiflorum [ 13 , 186 ], and Au-Ag nanoparticles have been produced from the Chinese wolfberry fruit extracts [ 187 ].…”