Porous platinum mesoflowers with enhanced activity for methanol oxidation reaction

Porous Pt and Pt–Ag alloy mesoflowers (MFs) with about 2 μm in diameter and high porosity were synthesized using Ag mesoflowers as sacrificial template by galvanic reaction. The silver content in Pt–Ag alloys can be facilely controlled by nitric acid treatment. And the pure Pt MFs can be obtained by selective removal of silver element from Pt72Ag28 MFs electrochemically. Both Pt45Ag55, Pt72Ag28 and pure Pt show a high catalytic performance in methanol oxidation reaction (MOR). Especially, pure Pt MFs exhibited a 2 to 3 times current density enhancement in MOR compared with the commercial used Pt black, which can be attributed to their porous nanostructure with 3-dimentional nature and small crystal sizes.

Graphical AbstractThe CVs of MOR on Pt (red) and Pt black (green) catalysts in 0.1 M HClO4 and 0.5 M CH3OH for specific mass current. The insert shows the SEM images of two porous Pt MFs. Platinum mesoflowers (MFs) with about 2 μm in diameter and high porosity were synthesised with Ag mesoflowers as sacrificial template by galvanic replacement. The porous Pt MFs exhibited a more than 3 times enhancement in electrocatalytic performance for methanol oxidation reaction compared the commercial used Pt black.Figure optionsDownload as PowerPoint slideHighlights
► Porous Pt and Pt–Ag mesoflowers (MFs) were synthesized using Ag MFs sacrifical template.
► Pt MFs presents an improved catalytic activity in MOR compared with Pt black.
► We provided a facile approach for the development of high performance Pt electrocatalysts for fuel cells.