pH induced size-selected synthesis of PtRu nanoparticles, their characterization and electrocatalytic properties

PtRu/C nanocatalysts with different size were prepared simply by adjusting the pH of β-d-glucose solution. Herein, β-d-glucose acts as a reducing agent as well as a capping agent. Transmission electron microscopy revealed that the well dispersed PtRu particles (12.7, 5.6, and 2.3 nm) were obtained at pH 8.5, 10.5, and 12.5, respectively. X-ray diffraction analysis indicated that the PtRu/C catalysts have different structures synthesized at different pH values. Only at pH 12.5, small amount of PtRu alloy was formed. X-ray photoelectron spectroscopy measurements showed that a large amount of Pt and Ru were present in metallic states. Both cyclic voltammetry and chronoamperometric results demonstrated that the PtRu/C catalyst prepared from the solution at pH 12.5 exhibited better performances for methanol electro-oxidation than the other samples.

Graphical abstractSize-selected PtRu/C nanocatalysts were synthesized in alkaline glucose solution by simply adjusting the pH. The PtRu particles become smaller and more uniform with the increase of alkaline glucose solution pH. PtRu/C exhibited better performances for methanol electro-oxidation than other samples when the synthesis solution pH was 12.5. Figure optionsDownload full-size imageDownload as PowerPoint slide