title: Spatially confined redox chemistry in periodic mesoporous hydridosilica-nanosilver grown in reducing nanopores.
abstract: Periodic mesoporous hydridosilica, PMHS, is shown for the first time to function as both a host and a mild reducing agent toward noble metal ions. In this archetypical study, PMHS microspheres react with aqueous Ag(I) solutions to form Ag(0) nanoparticles housed in different pore locations of the mesostructure. The dominant reductive nucleation and growth process involves SiH groups located within the pore walls and yields molecular scale Ag(0) nanoclusters trapped and stabilized in the pore walls of the PMHS microspheres that emit orange-red photoluminescence. Lesser processes initiated with pore surface SiH groups produce some larger spherical and worm-shaped Ag(0) nanoparticles within the pore voids and on the outer surfaces of the PMHS microspheres. The intrinsic reducing power demonstrated in this work for the pore walls of PMHS speaks well for a new genre of chemistry that benefits from the mesoscopic confinement of Si-H groups.
authors.affiliation: Department of Chemistry, Bilkent University, 06800, Ankara, Turkey. dag@fen.bilkent.edu.tr
authors.forename: Ömer
authors.initials: Ö
authors.lastname: Dag
authors.forename: Eric J
authors.initials: EJ
authors.lastname: Henderson
authors.forename: Wendong
authors.initials: W
authors.lastname: Wang
authors.forename: Jennifer E
authors.initials: JE
authors.lastname: Lofgreen
authors.forename: Srebri
authors.initials: S
authors.lastname: Petrov
authors.forename: Peter M
authors.initials: PM
authors.lastname: Brodersen
authors.forename: Geoffrey A
authors.initials: GA
authors.lastname: Ozin
mesh_terms: D053768:Metal Nanoparticles / Q000737:chemistry*; D058608:Nanopores; D017646:Organosilicon Compounds / Q000737:chemistry*; D010084:Oxidation-Reduction; D010316:Particle Size; D016062:Porosity; D012834:Silver / Q000737:chemistry*; D013499:Surface Properties
chemical_list: D017646:Organosilicon Compounds; D012834:Silver