Chemical insight into the origin of red and blue photoluminescence arising from freestanding silicon nanocrystals.
Mita Dasog,Zhenyu Yang,Sarah Regli,Tonya M. Atkins,Angelique Faramus,Mani P. Singh,Elayaraja Muthuswamy,Susan M. Kauzlarich,Richard D. Tilley,Jonathan G. C. Veinot +9 more
TLDR
Analysis of the evidence is consistent with the hypothesis that the presence of trace nitrogen and oxygen even at the parts per million level in Si NCs gives rise to the blue emission.Abstract:
Silicon nanocrystals (Si NCs) are attractive functional materials. They are compatible with standard electronics and communications platforms and are biocompatible. Numerous methods have been developed to realize size-controlled Si NC synthesis. While these procedures produce Si NCs that appear identical, their optical responses can differ dramatically. Si NCs prepared using high-temperature methods routinely exhibit photoluminescence agreeing with the effective mass approximation (EMA), while those prepared via solution methods exhibit blue emission that is somewhat independent of particle size. Despite many proposals, a definitive explanation for this difference has been elusive for no less than a decade. This apparent dichotomy brings into question our understanding of Si NC properties and potentially limits the scope of their application. The present contribution takes a substantial step forward toward identifying the origin of the blue emission that is not expected based upon EMA predictions. It desc...read more
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New Generation Cadmium-Free Quantum Dots for Biophotonics and Nanomedicine
TL;DR: This review summarizes recent progress in the design and applications of cadmium-free quantum dots (Cd-free QDs), with an emphasis on their role in biophotonics and nanomedicine.
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Synthesis of Semiconductor Nanocrystals, Focusing on Nontoxic and Earth-Abundant Materials.
Peter Reiss,Peter Reiss,Marie Carrière,Christophe Lincheneau,Christophe Lincheneau,Louis Vaure,Louis Vaure,Sudarsan Tamang +7 more
TL;DR: This work reviews the synthesis of semiconductor nanocrystals/colloidal quantum dots in organic solvents with special emphasis on earth-abundant and toxic heavy metal free compounds and a comprehensive overview on toxicity studies concerning all types of quantum dots.
Journal ArticleDOI
Colloidal silicon quantum dots: from preparation to the modification of self-assembled monolayers (SAMs) for bio-applications
TL;DR: Recent advances in the methods of preparing high quality silicon nanocrystals and strategies for forming self-assembled monolayers (SAMs) are summarized, with a focus on their bio-applications.
Journal ArticleDOI
Nonthermal Plasma Synthesis of Nanocrystals: Fundamental Principles, Materials, and Applications
Uwe Kortshagen,R. Mohan Sankaran,Rui N. Pereira,Rui N. Pereira,Steven L. Girshick,Jeslin J. Wu,Eray S. Aydil +6 more
TL;DR: The fundamentals of nanocrystal formation in plasmas are discussed, practical implementations of plasma reactors are reviewed, the materials that have been produced with nonthermal plAsmas and surface chemistries that have be developed are surveyed, and an overview of applications of plasma-synthesized nanocrystals is provided.
Journal ArticleDOI
Size vs surface: tuning the photoluminescence of freestanding silicon nanocrystals across the visible spectrum via surface groups.
TL;DR: Through rational variation in the surface moieties it is demonstrated that the photoluminescence of Si-NCs can be effectively tuned across the entire visible spectral region without changing particle size.
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