Market Overview:
Carbon dots (also called “carbon quantum dots”, “carbon nanodots”, etc.) represent a new class of photoactive nanomaterials that compete effectively with semiconductor quantum dots, a market that was valued at $961.4 million in 2013 and is projected to be larger than $5 billion in 2020. In addition to being benign and nontoxic, carbon dot performance is comparable to the much more expensive fullerene-based materials used in various optoelectronic devices. Carbon dots can be produced from abundant and environmentally-friendly precursors, and thus are suitable for low to ultralow cost applications. Carbon dots brightly fluoresce across the entire visible spectrum and near-IR, making them ideal for serving as fluorescence probes for bioimaging. The uniquely small size of quantum dots enables them to go anywhere in the body, making them suitable for bio-medical applications like medical imaging, biosensors, cell separation, etc.
Application Stage of Development
Healthcare &biotechnology research, general optic imaging Proof of Concept
Advantages
• Available in a wide variety of bright colors visible to the naked eye, making them ideal for medical imaging
• Small-sized with zero dimensionality, allowing them to be used anywhere within the body or electronic
devices
• Relatively inexpensive, reducing costs when compared to currently-used technologies
Technical Summary
This quantum dot technology can be comprised of a single material with uniform internal compositions, such as chalcogenides of metals like cadmium, lead or zinc. The photo- and electroluminescence properties of core-type quantum dots can be fine-tuned by simply changing crystallite size. The luminescent properties of quantum dots arise from the recombination of electron hole pairs through radiative pathways. However, excitation decay can also occur through non-radiative methods, reducing the fluorescence quantum yield. One of the methods used to improve efficiency and brightness of these semiconductor nanocrystals is growing shells of another, higher-band gap semiconducting material around them. These quantum dots with small regions of one material embedded in another with a wider band gap are known as core-shell quantum dots (CSQDs) or core-shell semiconducting nanocrystals (CSSNCs). Coating quantum dots with shells improves quantum yield by passivizing non-radiative recombination sites and also makes them more robust to processing conditions for various applications.
View printable PDF version of this technology
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Inventor: Dr. Ya-Ping Sun
Patent Type: Divisional
Serial Number 12/892,117
CURF Ref No: 2005-042