Department of Chemistry, Carnegie Mellon University , Pittsburgh, Pennsylvania 15213, United States.
Department of Chemistry, University of Pittsburgh , Pittsburgh, Pennsylvania 15213, United States.
ACS Nano. 2016 Sep 27;10(9):8385-93. doi: 10.1021/acsnano.6b03113. Epub 2016 Aug 30.
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.
硅纳米粒子（NPs）由于其内在的无毒、低成本和高丰度等优点，已被广泛接受为发光和生物成像应用中典型量子点和商业有机染料的替代材料。然而，迄今为止，如何提高硅纳米粒子的光致发光（PL）性能（如超高量子产率、尖锐发射峰、高稳定性）仍然是一个主要问题。在此，我们报告了表面氮封端的硅 NPs，其 PL 量子产率高达 90%，PL 带宽较窄（半峰全宽（fwhm）≈40nm），可与商业染料和典型量子点相媲美。我们进行了综合研究，揭示了颗粒尺寸、结构和表面配体数量对 Si NPs PL 的影响。特别是，在实验和理论分析中确定了基于表面氮封端 Si NPs 配体结构的一般 PL 能量定律，进一步讨论了其潜在的 PL 机制。
