title: Transition-Metal-Doped NIR-Emitting Silicon Nanocrystals.
abstract: Impurity-doping in nanocrystals significantly affects their electronic properties and diversifies their applications. Herein, we report the synthesis of transition metal (Mn, Ni, Co, Cu)-doped oleophilic silicon nanocrystals (SiNCs) through hydrolysis/polymerization of triethoxysilane with acidic aqueous metal salt solutions, followed by thermal disproportionation of the resulting gel into a doped-Si/SiO2composite that, upon HF etching and hydrosilylation with 1-n-octadecene, produces free-standing octadecyl-capped doped SiNCs (diameter≈3 to 8 nm; dopant <0.2 atom %). Metal-doping triggers a red-shift of the SiNC photoluminescence (PL) of up to 270 nm, while maintaining high PL quantum yield (26 % for Co doping).
authors.affiliation: WPI International Centre for Nanoarchitectonics (MANA), National Institute for Materials science (NIMS), 1-1 Namiki, Tsukuba, 305-0044, Japan.
authors.forename: Sourov
authors.initials: S
authors.lastname: Chandra
authors.affiliation: National Institute of Advanced Industrial Science and Technology (AIST), Shimoshidami, Moriyama, Nagoya, Japan.
authors.forename: Yoshitake
authors.initials: Y
authors.lastname: Masuda
authors.affiliation: WPI International Centre for Nanoarchitectonics (MANA), National Institute for Materials science (NIMS), 1-1 Namiki, Tsukuba, 305-0044, Japan.
authors.forename: Naoto
authors.initials: N
authors.lastname: Shirahata
authors.affiliation: WPI International Centre for Nanoarchitectonics (MANA), National Institute for Materials science (NIMS), 1-1 Namiki, Tsukuba, 305-0044, Japan.|Departement de Chimie, Universite de Montreal, CP 6128 Succursale Centre Ville, Montreal, QC, H3C 3J7, Canada.|Department of Chemistry and Faculty of Pharmacy, University of Helsinki, 00014, Helsinki, Finland.
authors.forename: Françoise M
authors.identifier: 0000-0001-5844-6687
authors.initials: FM
authors.lastname: Winnik
keywords: doping; nanocrystals; photoluminescence; silicon; thermal disproportionation