title: Templated assembly of Co-Pt nanoparticles via thermal and laser-induced dewetting of bilayer metal films.
abstract: Templated dewetting of a Co/Pt metal bilayer film on a topographic substrate was used to assemble arrays of Co-Pt alloy nanoparticles, with highly uniform particle size, shape and notably composition compared to nanoparticles formed on an untemplated substrate. Solid-state and liquid-state dewetting processes, using furnace annealing and laser irradiation respectively, were compared. Liquid state dewetting produced more uniform, conformal nanoparticles but they had a polycrystalline disordered fcc structure and relatively low magnetic coercivity. In contrast, solid state dewetting enabled formation of magnetically hard, ordered L1(0) Co-Pt single-crystal particles with coercivity >12 kOe. Furnace annealing converted the nanoparticles formed by liquid state dewetting into the L1(0) phase.
authors.affiliation: Department of Advanced Materials Science and Engineering, Hanbat National University, 125, Dongseo-daero, Yuseong-gu, Daejeon 305-719, Korea. yjoh@hanbat.ac.kr
authors.forename: Yong-Jun
authors.initials: YJ
authors.lastname: Oh
authors.forename: Jung-Hwan
authors.initials: JH
authors.lastname: Kim
authors.forename: Carl V
authors.initials: CV
authors.lastname: Thompson
authors.forename: Caroline A
authors.initials: CA
authors.lastname: Ross
mesh_terms: D003035:Cobalt / Q000737:chemistry* / Q000528:radiation effects; D003460:Crystallization / Q000379:methods*; D006358:Hot Temperature; D007834:Lasers; D046911:Macromolecular Substances / Q000737:chemistry; D008422:Materials Testing; D008567:Membranes, Artificial; D053768:Metal Nanoparticles / Q000737:chemistry* / Q000528:radiation effects / Q000648:ultrastructure; D008968:Molecular Conformation; D054802:Molecular Imprinting / Q000379:methods*; D010316:Particle Size; D010984:Platinum / Q000737:chemistry* / Q000528:radiation effects; D013499:Surface Properties; D017155:Wettability
chemical_list: D046911:Macromolecular Substances; D008567:Membranes, Artificial; D003035:Cobalt; D010984:Platinum