One-step synthesis of zero-dimensional hollow nanoporous gold nanoparticles with enhanced methanol electrooxidation performance

Abstract

Nanoporous gold with networks of interconnected ligaments and highly porous structure holds stimulating technological implications in fuel cell catalysis. Current syntheses of nanoporous gold mainly revolve around de-alloying approaches that are generally limited by stringent and harsh multistep protocols. Here we develop a one-step solution phase synthesis of zero-dimensional hollow nanoporous gold nanoparticles with tunable particle size (150-1,000 nm) and ligament thickness (21-54 nm). With faster mass diffusivity, excellent specific electroactive surface area and large density of highly active surface sites, our zero-dimensional nanoporous gold nanoparticles exhibit ~1.4 times enhanced catalytic activity and improved tolerance towards carbonaceous species, demonstrating their superiority over conventional nanoporous gold sheets. Detailed mechanistic study also reveals the crucial heteroepitaxial growth of gold on the surface of silver chloride templates, implying that our synthetic protocol is generic and may be extended to the synthesis of other nanoporous metals via different templates.

Electrically Bloomed Platinum Nanoflowers on Exfoliated Graphene: An Efficient Alcohol Oxidation Catalyst

“…Figure 6a shows two well-defined oxidation peaks characteristic for Pt/graphene methanol oxidation, ranging between −260 and −330 mV in the forward scan and another anodic peak ranging between −361 and −396 mV in the backward scan associated with the removal of residual carbonaceous species formed during the methanol oxidation in the forward scan. 22 In comparison with Pt/C catalysts, the potential peak values in both forward and backward scans for the Pt/graphene electrodes are more negative, indicating their superior performance. 23 Figure 6b shows that Pt/graphene electrodes have a better electrocatalytic activity when normalized by Pt loading.…”

Nanoporous gold film: fabrication and role as a catalytic reactor

“…1 It is attractive due to its high catalytic activity even when the featured length of ligaments is larger than 30 nm. 1 It is attractive due to its high catalytic activity even when the featured length of ligaments is larger than 30 nm.…”

Gold micromeshes as highly active electrocatalysts for methanol oxidation reaction

“…The stability is much better than those of other reported nanostructured Au, such as nanoporous Au nanoparticles with 150 nm particle sizes, whose peak current density decreases to 64% aer 480 cycles. 5 The number density of steps, kinks, twins, stacking faults, and dislocations in cycled Au micromeshes is reduced to 0.97 nm À1 , which is due to the increased radius of curvatures on the surface of Au micromeshes aer cycling ( Fig. S6c and d †).…”

“…In contrast, Au does not suffer from such poisoning, and is therefore considered as a more promising catalyst for MOR. 5,6 The electrocatalytic activity of Au depends on many factors such as size, 1,7 surface facet, 8 and defect 9,10 involving steps, kinks, stacking faults, twin boundaries, dislocations, etc. 11,12 These defects are considered as catalytically active sites due to their high surface energy, which promotes ionization and adsorption of intermediate reactants, such as OH À in electrolytes.…”