title: Toward atomically-precise synthesis of supported bimetallic nanoparticles using atomic layer deposition.
abstract: Multi-metallic nanoparticles constitute a new class of materials offering the opportunity to tune the properties via the composition, atomic ordering and size. In particular, supported bimetallic nanoparticles have generated intense interest in catalysis and electrocatalysis. However, traditional synthesis methods often lack precise control, yielding a mixture of monometallic and bimetallic particles with various compositions. Here we report a general strategy for synthesizing supported bimetallic nanoparticles by atomic layer deposition, where monometallic nanoparticle formation is avoided by selectively growing the secondary metal on the primary metal nanoparticle but not on the support; meanwhile, the size, composition and structure of the bimetallic nanoparticles are precisely controlled by tailoring the precursor pulse sequence. Such exquisite control is clearly demonstrated through in situ Fourier transform infrared spectroscopy of CO chemisorption by mapping the gradual atomic-scale evolution in the surface composition, and further confirmed using aberration-corrected scanning transmission electron microscopy.
authors: Department of Chemical Physics, University of Science and Technology of China, Hefei 230026, China.
authors: Junling
authors: J
authors: Lu
authors: Research Resources Center, University of Illinois at Chicago, Chicago, Illinois 60607, USA.
authors: Ke-Bin
authors: KB
authors: Low
authors: Energy Systems Division, Argonne National Laboratory, Argonne, Illinois 60439, USA.
authors: Yu
authors: Y
authors: Lei
authors: Energy Systems Division, Argonne National Laboratory, Argonne, Illinois 60439, USA.
authors: Joseph A
authors: JA
authors: Libera
authors: Research Resources Center, University of Illinois at Chicago, Chicago, Illinois 60607, USA.
authors: Alan
authors: A
authors: Nicholls
authors: 1] Chemical Sciences & Engineering Division, Argonne National Laboratory, Argonne, Illinois 60439, USA [2] Department of Chemistry, Northwestern University, Evanston, Illinois 60208, USA.
authors: Peter C
authors: PC
authors: Stair
authors: Energy Systems Division, Argonne National Laboratory, Argonne, Illinois 60439, USA.
authors: Jeffrey W
authors: JW
authors: Elam