Quantum Dots (QDs)

Quantum dots (QDs) are nanoscale semiconductor particles that exhibit unique optical and electronic properties due to quantum confinement effects. These nanocrystals, typically composed of elements from groups II-VI, III-V, or IV-VI, possess size-dependent fluorescence, high quantum yield, and excellent photostability, making them invaluable for applications in biomedical imaging, optoelectronics, and photovoltaics.

Classification

The types of QDs we can offer our customers are:

• Oil-Soluble QDs

Oil-soluble QDs are semiconductor nanocrystals that exhibit excellent photoluminescence and tunable optical properties. These QDs are typically surface-functionalized with hydrophobic ligands, making them highly dispersible in nonpolar solvents such as toluene, hexane, or chloroform. Due to their strong fluorescence, narrow emission spectra, and broad absorption profiles, oil-soluble QDs are widely utilized in optoelectronic applications, including display technologies, light-emitting diodes (LEDs), and photovoltaic devices. Additionally, they are valuable in bioimaging applications where lipid-based environments or organic phases are required.

• Water-Soluble QDs

Water-soluble QDs are semiconductor nanocrystals engineered with hydrophilic surface modifications, allowing them to disperse stably in aqueous environments. These modifications often involve carboxyl (-COOH), amine (-NH₂), or polyethylene glycol (PEG), which enhance their biocompatibility and minimize aggregation in physiological conditions. With their bright fluorescence, excellent photostability, and narrow emission spectra, water-soluble QDs are widely applied in bioimaging, biosensing, and medical diagnostics.

• Quantum Dot (QD) Microspheres

QD microspheres are assembled by quantum dot luminescent materials and nano-scale microspheres with functional groups on the surface. These microspheres combine the superior optical properties of QDs, such as high quantum yield, tunable fluorescence, and excellent photostability, with the controlled size distribution and surface chemistry of microspheres. Their functionalized surfaces enable targeted conjugation with biomolecules, making them ideal for applications in bioimaging, immunoassays, flow cytometry, and optical barcoding.

Applications

Quantum dots have revolutionized multiple fields due to their exceptional optical, electronic, and structural characteristics. Key application areas include:

• Biomedical Imaging and Therapy: QDs enable high-resolution imaging of live cells and tissues, offering advantages over organic dyes in terms of brightness and photostability. Functionalized QDs are also explored for targeted drug delivery and photothermal therapy.
• Quantum Dot Solar Cells (QDSCs): QDs can enhance light absorption in photovoltaic devices and enable multiple exciton generation (MEG), thereby increasing power conversion efficiency. PbS and CdTe QDs are widely investigated for next-generation solar energy harvesting.
• Light-Emitting Devices and Displays: QDs have revolutionized light-emitting devices and display technologies by offering exceptional color purity, tunable emission, and high energy efficiency. For example, in quantum dot light-emitting diodes (QLEDs), QDs serve as emissive layers, enabling wider color gamuts, higher brightness, and longer lifespans compared to traditional organic light-emitting diodes (OLEDs) and liquid crystal displays (LCDs).
• Environmental and Chemical Sensing: QD-based sensors detect heavy metals, toxins, and biological contaminants with high specificity and sensitivity, aiding in environmental monitoring and food safety.

Our Products

Alfa Chemistry, a leading provider of advanced nanomaterials, offers a diverse range of QDs tailored for research and industrial applications, ensuring high purity, stability, and customizable surface functionalities. If you are interested in our products, please feel free to contact us.