Catalytic Performances of Au–Pt Nanoparticles on Phosphorous Functionalized Carbon Nanofibers towards HMF Oxidation

Abstract

Herein, we reported the utilization of pre-formed Au–Pt nanoparticles deposited on phosphorus functionalized carbons as effective catalysts for the oxidation of 5-hydroxymethylfurfural (HMF) to furandicarboxylic acid (FDCA). Au–Pt nanoparticles have been prepared by a two-step methodology using polyvinyl alcohol (PVA) as protective agent and a combination of NaBH4 and H2 as reducing agents. Three carbon nanofibers (CNFs) with different graphitization degrees have been functionalized through treatment with an H3PO4–HNO3 mixture at 150 °C, in order to incorporate P groups on carbon surface. Surface and structural properties of the synthesized functionalized materials have been investigated by transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and Raman spectroscopy. The structural and surface properties of carbon nanofibers determine the amount of P-functionalities, which is a key parameter affecting the catalytic performances of Au–Pt. Indeed, the highest activity and stability has been achieved for Au–Pt deposited on the sample, which showed the largest amount of P-groups on the surface.

Enhancing activity, selectivity and stability of palladium catalysts in formic acid decomposition: Effect of support functionalization

“…Danis demonstrated that, among all, SV is the most reactive defect towards the addition of an heteroatoms functional group [64]. Based on the typical functional groups found on the carbon surface after a standard functionalization procedure [26,53,65,66], five different functionalization groups were anchored on the SV, i.e. carboxyl (G_COOH), hydroxyl (G_OH), carbonyl (G_CO) and phosphate (G_PO3H) groups (Figure 5).…”

“…The electronic structure of these catalysts is also affected improving their activity in reactions such as hydrodeoxygenation [23], electrocatalytic oxygen reduction [24], photocatalytic oxidation [25]. Oxygen as a dopant influences the charge transfer between carbon and metal nanoparticles, in fact, most heteroatoms enhance the electron density of the neighbouring carbon atoms increasing the back-donation from C to the metal atoms [26]. Nitrogen and boron doped C-materials have received an increasing consideration as they directly affect the Fermi level of the solid [27,28], and Pd and Pd alloyed NPs supported on them showed promising activity and durability during FA decomposition reaction [29][30][31][32].…”

Oxidation of 5-Hydroxymethylfurfural on Supported Ag, Au, Pd and Bimetallic Pd-Au Catalysts: Effect of the Support

“…Table 1 presents screening of Au-, Ag-, Pd-based and PdAu heterogeneous catalysts for aqueous liquid phase oxidation of HMF under the reaction conditions reported in previous studies (0.15 M HMF, HMF/metal: 200 mol/mol, 60 • C, 3 bar O 2 , 2 equiv. NaOH, 2 h) [17,18].…”

“…Supported catalysts based on noble metals (Pd, Pt, Ru or Au) [9][10][11][12][13][14] or their combination (bimetallic systems) [15][16][17][18] have demonstrated high activity and selectivity for HMF oxidation. However, their catalytic activity is strongly sensitive to many factors, such as metal dispersion, preparation method, nature of the support, metal-support interaction, etc.…”

Mechanistic insights into the selective oxidation of 5-(hydroxymethyl)furfural over silver-based catalysts

“…Many studies focus on the synthesis of FDCA and the routes range from stoichiometric chemical transformations 10 to bio-, 11,12 electro- [13][14][15] or heterogeneous metal catalysts. In the latter case, mostly noble metals like Pd, [16][17][18] Pt, [19][20][21] Au [22][23][24][25] or alloys thereof [26][27][28] show high activity.…”