Rational Construction of Strongly Coupled Metal–Metal Oxide–Graphene Nanostructure with Excellent Electrocatalytic Activity and Durability

Abstract

The interaction within heterogeneous nanostructures can provide a great opportunity to radically enhance their electrocatalytic properties and increase their activity and durability. Here a rational, simple, and integrated strategy is reported to construct uniform and strongly coupled metal-metal oxide-graphene nanostructure as an electrocatalyst with high performance. We first simply synthesized the interacted SnO2-prGO (protected and reduced graphene oxide) hybrid with SnO2 nanoparticles (∼4 nm) selectively anchored on the oxygenated defects of rGO using an in situ redox and hydrolysis reaction. After the deposition of Pt, uniform Pt NPs are found to contact intimately and exclusively with the SnO2 phase in the SnO2-prGO hybrid. This constructed nanostructure (Pt-SnO2-prGO) exhibits significantly improved electrocatalytic activity (2.19-fold) and durability (2.08-fold) toward methanol oxidation over that of the state-of-the-art Pt/C catalyst. The detailed explanation of the strong coupling between SnO2 and graphene as well as between Pt and SnO2 is discussed, revealing that such a process can be used to immobilize various metal catalysts on metal-oxide-decorated catalysts for realizing advanced catalytic systems with enhanced performance.

Fabrication of SnO2–SnO nanocomposites with p–n heterojunctions for the low-temperature sensing of NO2 gas

“…1C shows the high-resolution O1s spectrum of the hybrid, in which the deconvoluted two peaks at 45 binding energies of 529.9 and 531.2 eV correspond to the SnO 2 (Sn-O-Sn) and the oxygen of SnO (Sn=O), respectively. 48 The XPS results agree well with that of the XRD measurements. Both XRD and XPS characterizations indicate that SnO 2 -SnO hybrid has been successfully fabricated through the hydrothermal 50 process.…”

A Vanadium(V) Oxide Nanorod Promoted Platinum/Reduced Graphene Oxide Electrocatalyst for Alcohol Oxidation under Acidic Conditions

“…Recently, the activity of Pt electrocatalysts was improved by adding metal oxides, sulfides, carbides, and nitrides as promoters . Among them, metal‐oxide promoters are more efficient because they provide hydroxy sources for removal of carbonaceous species, such as adsorbed CO (CO ads ), at lower potentials . Also, metal oxides stabilize Pt crystallites and avoid their random growth and accumulation during device operation for longer times.…”

Facile Synthesis of Bimetallic Pt-Ag/Graphene Composite and Its Electro-Photo-Synergistic Catalytic Properties for Methanol Oxidation

“…As shown in Figure 8, the Nyquist plots of EIS for Pt-Ag/GNs, Pt/GNs and Pt/C-JM were obtained in 0.5 M H2SO4 + 1.0 M CH3OH solution at 0.5 V. The diameter of the primary semicircle can be used to analyze the charge transfer resistance of the catalyst, which describes the rate of charge transfer during the methanol oxidation reaction [32]. The semicircle radius of Pt-Ag/GNs (curve c) is much smaller than that of Pt/GNs (curve b) and Pt/C-JM (curve a), which illustrates that Pt-Ag/GNs have better charge transfer and a faster methanol oxidation reaction rate [33,34]. The ECSA values for the Pt-Ag/GNs (curve c) is 120.3 m 2 ·g −1 , which is about 1.5 times and 2.5 times higher than that of the Pt/GNs (curve b) (80.5 m 2 ·g −1 ) and the Pt/C-JM (curve a) (48.9 m 2 ·g −1 ), respectively.…”