title: Silicon Nanoparticles with Surface Nitrogen: 90% Quantum Yield with Narrow Luminescence Bandwidth and the Ligand Structure Based Energy Law.
abstract: Silicon nanoparticles (NPs) have been widely accepted as an alternative material for typical quantum dots and commercial organic dyes in light-emitting and bioimaging applications owing to silicon's intrinsic merits of least toxicity, low cost, and high abundance. However, to date, how to improve Si nanoparticle photoluminescence (PL) performance (such as ultrahigh quantum yield, sharp emission peak, high stability) is still a major issue. Herein, we report surface nitrogen-capped Si NPs with PL quantum yield up to 90% and narrow PL bandwidth (full width at half-maximum (fwhm) ≈ 40 nm), which can compete with commercial dyes and typical quantum dots. Comprehensive studies have been conducted to unveil the influence of particle size, structure, and amount of surface ligand on the PL of Si NPs. Especially, a general ligand-structure-based PL energy law for surface nitrogen-capped Si NPs is identified in both experimental and theoretical analyses, and the underlying PL mechanisms are further discussed.
authors.affiliation: Department of Chemistry, Carnegie Mellon University , Pittsburgh, Pennsylvania 15213, United States.
authors.forename: Qi
authors.initials: Q
authors.lastname: Li
authors.affiliation: Department of Chemistry, University of Pittsburgh , Pittsburgh, Pennsylvania 15213, United States.
authors.forename: Tian-Yi
authors.initials: TY
authors.lastname: Luo
authors.affiliation: Department of Chemistry, Carnegie Mellon University , Pittsburgh, Pennsylvania 15213, United States.
authors.forename: Meng
authors.initials: M
authors.lastname: Zhou
authors.affiliation: Department of Chemistry, Carnegie Mellon University , Pittsburgh, Pennsylvania 15213, United States.
authors.forename: Hadi
authors.initials: H
authors.lastname: Abroshan
authors.affiliation: State Key Laboratory of Molecular Engineering of Polymers, Advanced Material Laboratory, Department of Macromolecular Science, Fudan University , Shanghai 200433, People's Republic of China.
authors.forename: Jingchun
authors.initials: J
authors.lastname: Huang
authors.affiliation: Department of Chemistry, Carnegie Mellon University , Pittsburgh, Pennsylvania 15213, United States.|School of Computational Sciences, Korea Institute for Advanced Study , Seoul 02455, Korea.
authors.forename: Hyung J
authors.initials: HJ
authors.lastname: Kim
authors.affiliation: Department of Chemistry, University of Pittsburgh , Pittsburgh, Pennsylvania 15213, United States.
authors.forename: Nathaniel L
authors.initials: NL
authors.lastname: Rosi
authors.affiliation: State Key Laboratory of Molecular Engineering of Polymers, Advanced Material Laboratory, Department of Macromolecular Science, Fudan University , Shanghai 200433, People's Republic of China.
authors.forename: Zhengzhong
authors.initials: Z
authors.lastname: Shao
authors.affiliation: Department of Chemistry, Carnegie Mellon University , Pittsburgh, Pennsylvania 15213, United States.
authors.forename: Rongchao
authors.initials: R
authors.lastname: Jin
keywords: PL energy law; narrow bandwidth; quantum dots; silicon nanoparticles; ultrabright fluorescence