Crystal phase can greatly affect the physicochemical properties and applications of nanomaterials.However,it stil remains a great challenge to synthesize nanostructures with the same composition and morphology but dif...Crystal phase can greatly affect the physicochemical properties and applications of nanomaterials.However,it stil remains a great challenge to synthesize nanostructures with the same composition and morphology but different phases in order to explore the phase-dependent properties and applications.Herein,we report the crystal phase-controlled synthesis of PtCu alloy shells on 4H Au nanoribbons(NRBs),referred to as 4H-Au NRBs,to form the 4H-Au@PtCu core-shell NRBs.By tuning the thickness of PtCu,4H-PtCu and face-centered cubic(cc)phase PICu(cc-PtCu)alloy shells are successtully grown on the 4H-Au NRB cores.This thickness-dependent phase-controlled growth strategy can also be used to grow PtCo alloys with 4H or fcc phase on 4H-Au NRBs.Significantly,when used as electrocatalysts for the ethanol oxidation reaction(EOR)in alkaline media,the 4H-Au@4H-PtCu NRBs show much better EOR performance than the 4H-Au@fcc-PtCu NRBs,and both of them possess superior performance compared to the commercial Pt black.Our study provides a strategy on phase-contolled synthesis of nanomaterials used for crystal phase-dependent applications.展开更多
基金MOE under AcRF Tier 2(Nos.MOE2016-T2-2-103 and MOE2017-T2-1-162)NTU under Start-Up Grant(No.M4081296.070.500000)in Singapore+2 种基金We would like to acknowledge the Facility for Analysis,Characterization,Testing and Simulation,Nanyang Technological University,Singapore,for use of their electron microscopy and X-ray facilities.Z.X.F.and H.Z.thank the financial support from ITC via Hong Kong Branch of National Precious Metals Material Engineering Research Center(NPMM)acknowledge the start-up grants(Nos.9380100,9610480 and 7200651)grants(Nos.9610478 and 1886921)in City University of Hong Kong.
文摘Crystal phase can greatly affect the physicochemical properties and applications of nanomaterials.However,it stil remains a great challenge to synthesize nanostructures with the same composition and morphology but different phases in order to explore the phase-dependent properties and applications.Herein,we report the crystal phase-controlled synthesis of PtCu alloy shells on 4H Au nanoribbons(NRBs),referred to as 4H-Au NRBs,to form the 4H-Au@PtCu core-shell NRBs.By tuning the thickness of PtCu,4H-PtCu and face-centered cubic(cc)phase PICu(cc-PtCu)alloy shells are successtully grown on the 4H-Au NRB cores.This thickness-dependent phase-controlled growth strategy can also be used to grow PtCo alloys with 4H or fcc phase on 4H-Au NRBs.Significantly,when used as electrocatalysts for the ethanol oxidation reaction(EOR)in alkaline media,the 4H-Au@4H-PtCu NRBs show much better EOR performance than the 4H-Au@fcc-PtCu NRBs,and both of them possess superior performance compared to the commercial Pt black.Our study provides a strategy on phase-contolled synthesis of nanomaterials used for crystal phase-dependent applications.