Coupling Ultrafine Pt Nanocrystals over the Fe₂P Surface as a Robust Catalyst for Alcohol Fuel Electro-Oxidation

Abstract

Ultrafine Pt nanocrystals with an average particle size of 2.2 ± 1 nm coupled over the petaloid Fe 2 P surface are proposed as a novel, efficient, and robust catalyst for alcohol fuel electro-oxidation. The strong coupling effect of metal−support imparts a strong electronic interaction between the Fe 2 P and Pt interface that can weaken the adsorption of poisoning CO species according to the d-band theory. Defects and increased surface area of the petaloid Fe 2 P are beneficial to the Pt nanoparticle anchoring and dispersion as well as the charge transfer and reactant transportation during the electrochemical reaction. These features make the Pt−Fe 2 P catalyst system exhibit excellent catalytic activity, antipoisoning ability, and catalytic stability for alcohol fuel of methanol and ethanol electro-oxidation compared with a controlled Pt/C catalyst. The high catalytic efficiency is proposed to come from the strong coupling effect of Pt and petaloid Fe 2 P interface that can maintain the mechanical and chemical stability of the catalyst system. This kind of phosphide-supported ultrafine Pt nanocrystals will be a promising catalyst in fuel cells.

Bimetallic Pd96Fe4 nanodendrites embedded in graphitic carbon nanosheets as highly efficient anode electrocatalysts

“…20,95,96 Additionally, the highly active sites and large effective surface area of carbon nanosheets with a graphene-like layered structure shorten paths for fast electrolyte ion diffusion, consequently offering more electron/charge transfer channels within the nanohybrid materials during catalysis. [97][98][99] Furthermore, the combination of graphitic nanosheets with metal nanostructures leads to the protection of the metal nanocluster from further aggregation and provides superior catalytic activity, and can be extended as a scalable, clean approach without using any chemical reducing agents via radiolysis. During ethanol oxidation, initially ethanol may adsorb on the electrode surface followed by oxidation and decomposition to generate intermediates such as acetate (CH 3 COO À ), acetaldehyde (CH 3 CHO), and CO. 5 In order to shed light on anodic oxidation of ethanol, a cyclic voltammetric study was carried out using Pd 96 Fe 4 /GCN electrodes immersed in 0.5 M KOH with sodium acetate, acetaldehyde and ethanol fuels (100 mM).…”

Advanced Catalytic Materials for Ethanol Oxidation in Direct Ethanol Fuel Cells

“…In general, it is difficult to maximize the activity of Pt-based catalysts by simple phosphorus doping due to its limited doping concentration [62]. On account of this, various transition metal phosphides have been developed as catalysts promoters that can help suppress the poisoning effect in the oxidation process of fuels, including formic acid [63], methanol [64], and ethanol [58,59]. For instance, Pt-Fe 2 P catalysts with petal-like structures and anchored Pt nanoparticles (~2 nm) were synthesized by microwave-assisted alcohol reduction method [59].…”

“…On account of this, various transition metal phosphides have been developed as catalysts promoters that can help suppress the poisoning effect in the oxidation process of fuels, including formic acid [63], methanol [64], and ethanol [58,59]. For instance, Pt-Fe 2 P catalysts with petal-like structures and anchored Pt nanoparticles (~2 nm) were synthesized by microwave-assisted alcohol reduction method [59]. The hybrid catalysts showed excellent catalytic activity,~3-fold that of the control Pt/C catalyst, and highly improved stability over the Pt/C catalyst.…”

“…Recent studies have been extended to develop diverse alternatives to replace the carbon black, such as carbon nanotubes, graphene, metal oxides, metal hydroxides, and their hybrids. Moreover, a few self-supported promoters have also been developed, such as Fe 2 P [59], W 2 C [70], and MoS 2 [76]. Further, flexible and conductivity substrates can also serve as promising supports for Pt-and Pd-based catalysts.…”

Cross-linked polyfuran networks with elastomeric behaviour based on humins biorefinery by-products

“…Recently, researchers started to explore possible routes to valorize this by-product derived from biomass conversion processes in order to turn them into high-value products. Kang et al 24 have completely degraded humins by alkaline-catalytic hydrothermal treatment followed by wet oxidation. By this technology, the authors managed to convert humins into acetic acid obtaining a yield of 25.6% and a purity of 46.2%.…”