title: Controlled growth of platinum nanoparticles on strontium titanate nanocubes by atomic layer deposition.
abstract: With an eye toward using surface morphology to enhance heterogeneous catalysis, Pt nanoparticles are grown by atomic layer deposition (ALD) on the surfaces of SrTiO(3) nanocubes. The size, dispersion, and chemical state of the Pt nanoparticles are controlled by the number of ALD growth cycles. The SrTiO(3) nanocubes average 60 nm on a side with {001} faces. The Pt loading increases linearly with Pt ALD cycles to a value of 1.1 x 10(-6) g cm(-2) after five cycles. Scanning electron microscopy images reveal discrete, well-dispersed Pt nanoparticles. Small- and wide-angle X-ray scattering show that the Pt nanoparticle spacing and size increase as the number of ALD cycles increases. X-ray absorption spectroscopy shows a progression from platinum(II) oxide to metallic platinum and a decrease in Pt--O bonding with an increase in Pt--Pt bonding as the number of ALD cycles increases.
authors.affiliation: Department of Materials Science and Engineering Northwestern University Evanston, IL 60208-3108, USA.
authors.forename: Steven T
authors.initials: ST
authors.lastname: Christensen
authors.forename: Jeffrey W
authors.initials: JW
authors.lastname: Elam
authors.forename: Federico A
authors.initials: FA
authors.lastname: Rabuffetti
authors.forename: Qing
authors.initials: Q
authors.lastname: Ma
authors.forename: Steven J
authors.initials: SJ
authors.lastname: Weigand
authors.forename: Byeongdu
authors.initials: B
authors.lastname: Lee
authors.forename: Soenke
authors.initials: S
authors.lastname: Seifert
authors.forename: Peter C
authors.initials: PC
authors.lastname: Stair
authors.forename: Kenneth R
authors.initials: KR
authors.lastname: Poeppelmeier
authors.forename: Mark C
authors.initials: MC
authors.lastname: Hersam
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Bedzyk
mesh_terms: D003460:Crystallization / Q000379:methods*; D046911:Macromolecular Substances / Q000737:chemistry; D008422:Materials Testing; D008968:Molecular Conformation; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure*; D036103:Nanotechnology / Q000379:methods*; D010087:Oxides / Q000737:chemistry*; D010316:Particle Size; D010984:Platinum / Q000737:chemistry*; D013324:Strontium / Q000737:chemistry*; D013499:Surface Properties; D014025:Titanium / Q000737:chemistry*
chemical_list: D046911:Macromolecular Substances; D010087:Oxides; D010984:Platinum; D014025:Titanium; C119252:strontium titanium oxide; D013324:Strontium