Template‐ and Surfactant‐Free Room Temperature Synthesis of Pt/C and Pt−Rh/C Nanowires/Nanoparticles for Ethanol Electro‐Oxidation

Abstract

The synthesis of Pt−Rh alloy nanowires (NWs) using straightforward methodologies remains a challenge. Here, carbon‐supported Pt and Pt−Rh nanowire catalysts were synthesised by chemical reduction at room temperature, without using surfactants or templates. The method of synthesis used yielded Pt/C NWs and a mixture of nanowires with some nanoparticles for the Pt−Rh/C catalysts (characterised using XRD, TEM, EDX, XPS, and XAS). The nanoparticles form due to differences in the surface energy and atomic radius between Pt and Rh. The binary NWs are found to be more active towards ethanol oxidation than the commercial Pt/C reference catalyst. Additionally, the Pt−Rh/C NW catalyst displays a specific activity 2.5‐fold higher than the Pt/C NWs and Pt/C reference catalysts after 15 min of chronoamperometric tests (at 0.5 V vs RHE). Thus, the synthesised carbon‐supported Pt NWs and Pt−Rh nanowires‐nanoparticles are promising alternatives for direct ethanol fuel cell anodes.

Fibrous Material Structure Developments for Sustainable Heterogeneous Catalysis – An Overview

“…Compared to typical spherical nanoparticles, the nm thickness and μm length of nanowires can overcome several drawbacks due to their high surface-to-volume ratio, the long segments of smooth crystal planes, and fewer surface defect sites. [84] The very high aspect ratio provides numerous catalytic sites for reaction and actively prevents dissolution and aggregation of the active sites. [85][86][87] An interesting example is the development of Pt-based ultrafine nanowires for applications in renewable energy-related devices.…”

Pd11Ni11Pt2 nanoparticles with three-phase surface enrichment for facilitating electrooxidation of ethanol and ethylene glycol

“…1–7 Compared with methanol, ethanol and ethylene glycol possess the advantages of high theoretical energy density, low toxicity, a high boiling point, low membrane penetration, and safe storage. 8–10 Unfortunately, for the EOR and EGOR, the sluggish reaction kinetics and low output power density still cannot meet the actual demand of fuel cells. Pd-based materials are generally regarded as one of the most effective catalysts to improve the performance of ethanol and ethylene glycol electrooxidation because of their electronic structure similar to that of Pt.…”

Electrochemical Oxidation of Ethanol and Methanol at Rh@Pt Catalysts at 80 °C in Proton Exchange Membrane (PEM) Cells

“…There are many reports that PtRh alloy nanoparticles show enhanced selectivity for production of CO 2 from ethanol, relative to pure Pt, due to the strong ability of Rh to activate C-C dissociation. [35][36][37][38][39][40][41][42][43][44][45][46][47][48][49] Additionally, PtRh nanoparticles are very stable in harsh operating environments. 50 However, the effectiveness of Rh for promoting C-C bond cleavage during ethanol oxidation at ambient temperature has recently been questioned, 9 and the relevance of these studies to ethanol oxidation in PEM cells at elevated temperatures is unclear.…”