title: Bimetallic Au-Ni nanoparticles embedded in SiO2 nanospheres: synergetic catalysis in hydrolytic dehydrogenation of ammonia borane.
abstract: Gold-nickel nanoparticles (NPs) of 3-4 nm diameter embedded in silica nanospheres of around 15 nm have been prepared by using [Au(en)(2)Cl(3)] and [Ni(NH(3))(6)Cl(2)] as precursors in a NP-5/cyclohexane reversed-micelle system, and by in situ reduction in an aqueous solution of NaBH(4)/NH(3)BH(3). Compared with monometallic Au@SiO(2) and Ni@SiO(2), the as-synthesized Au-Ni@SiO(2) catalyst shows higher catalytic activity and better durability in the hydrolysis of ammonia borane, generating a nearly stoichiometric amount of hydrogen. During the generation of H(2), the synergy effect between gold and nickel is apparent: The nickel species stabilizes the gold NPs and the existence of gold helps to improve the catalytic activity and durability of the nickel NPs.
authors.affiliation: National Institute of Advanced Industrial Science and Technology (AIST), Ikeda, Osaka 563-8577, Japan.
authors.forename: Hai-Long
authors.initials: HL
authors.lastname: Jiang
authors.forename: Tetsuo
authors.initials: T
authors.lastname: Umegaki
authors.forename: Tomoki
authors.initials: T
authors.lastname: Akita
authors.forename: Xin-Bo
authors.initials: XB
authors.lastname: Zhang
authors.forename: Masatake
authors.initials: M
authors.lastname: Haruta
authors.forename: Qiang
authors.initials: Q
authors.lastname: Xu