Bimetallic PtAu heteronanostructures have been synthesized from Pt-on-Au nanoparticles,which were made from platinum acetylacetonate and gold nanoparticles.Using the Pt-on-Au nanoparticles as precursors,Pt-surface ric...Bimetallic PtAu heteronanostructures have been synthesized from Pt-on-Au nanoparticles,which were made from platinum acetylacetonate and gold nanoparticles.Using the Pt-on-Au nanoparticles as precursors,Pt-surface rich PtAu bimetallic heteronanostructures can be produced through controlled thermal treatments,as confirmed by field emission high-resolution transmission electron microscopy(HR-TEM)and elemental mapping using a high-angle annular dark-field scanning transmission electron microscope(HAADF-STEM).Oxidation of formic acid was used as a model reaction to demonstrate the effects of varying composition and surface structure on the catalytic performance of PtAu bimetallic nanostructures.Cyclic voltammetry(CV)showed that these carbon-supported PtAu heteronanostructures were much more active than platinum in catalyzing the oxidation of formic acid,judging by the mass current density.The results showed that post-synthesis modification can be a very useful approach to the control of composition distributions in alloy nanostructures.展开更多
Development of active and durable electro- catalyst for oxygen reduction reaction （ORR） remains one challenge for the polymer electrolyte membrane fuel cell （PEMFC） technology. Pt-based nanomaterials show the grea...Development of active and durable electro- catalyst for oxygen reduction reaction （ORR） remains one challenge for the polymer electrolyte membrane fuel cell （PEMFC） technology. Pt-based nanomaterials show the greatest promise as electrocatalyst for this reaction among all current catalytic structures. This review focuses on Pt- based ORR catalyst material development and covers the past achievements, current research status and perspectives in this research field. In particular, several important categories of Pt-based catalytic structures and the research advances are summarized. Key factors affecting the catalyst activity and durability are discussed. An outlook of future research direction of ORR catalyst research is provided.展开更多
基金U.S.National Science Foundation(DMR-0449849)It made use of Shared Experimental Facilities at the University of Rochester River Campus Electron Microscope Lab and at the Cornell Center for Materials Research(CCMR)supported by NSF.We thank Mr.Hongjun You for help.
文摘Bimetallic PtAu heteronanostructures have been synthesized from Pt-on-Au nanoparticles,which were made from platinum acetylacetonate and gold nanoparticles.Using the Pt-on-Au nanoparticles as precursors,Pt-surface rich PtAu bimetallic heteronanostructures can be produced through controlled thermal treatments,as confirmed by field emission high-resolution transmission electron microscopy(HR-TEM)and elemental mapping using a high-angle annular dark-field scanning transmission electron microscope(HAADF-STEM).Oxidation of formic acid was used as a model reaction to demonstrate the effects of varying composition and surface structure on the catalytic performance of PtAu bimetallic nanostructures.Cyclic voltammetry(CV)showed that these carbon-supported PtAu heteronanostructures were much more active than platinum in catalyzing the oxidation of formic acid,judging by the mass current density.The results showed that post-synthesis modification can be a very useful approach to the control of composition distributions in alloy nanostructures.
文摘Development of active and durable electro- catalyst for oxygen reduction reaction （ORR） remains one challenge for the polymer electrolyte membrane fuel cell （PEMFC） technology. Pt-based nanomaterials show the greatest promise as electrocatalyst for this reaction among all current catalytic structures. This review focuses on Pt- based ORR catalyst material development and covers the past achievements, current research status and perspectives in this research field. In particular, several important categories of Pt-based catalytic structures and the research advances are summarized. Key factors affecting the catalyst activity and durability are discussed. An outlook of future research direction of ORR catalyst research is provided.
