Emission peculiarities of high-quantum yield silicon nanoparticles

March 13, 2014
Emission peculiarities of high-quantum yield silicon nanoparticles
Figure 1. Photographs (top) and emission spectra (bottom) of silicon quantum dots suspended in methanol. Emission spectra gradually shift from near-infrared to red with decreasing particle size, which is achieved simply by annealing the as-prepared material at different temperatures. Credit: American Chemical Society.

In 1990, scientists reported that nanostructured silicon can emit visible light. This report opened a new frontier for photoelectronics in information technology, called "silicon photonics". Furthermore, the continuous tuning of electromagnetic emission from near-UV to near-infrared wavelengths has been achieved by controlling silicon nanostructures.

The (QY) of this radiation may exceed 70%, and the use of silicon as the emitting material is advantageous because of its abundance and low toxicity to the human body and environment.

These advantages have been expected to stimulate the use of luminescent silicon in various fields; however, commercial applications are still lacking.

In this paper, Ghosh and Shirahata focus on high-QY silicon nanoparticles. It summarizes the peculiarities of their emission, which depends on the preparation method and surface chemistry.

In particular, there are two spectral ranges separated by green light, which can not be smoothly covered using a single synthesis approach. This green boundary is discussed to provide a better understanding of the emission mechanisms.

Those mechanisms are summarized to ascertain the future challenges in the industrial use of silicon-based light emitters. The authors believe that silicon nanophotonics is still in its infancy.

They predict that with high-quality materials of narrow size distribution and controlled surface chemistry in hand, novel photonic structures will be realized in the near future, including biomedical imaging devices, optical amplifiers, sensors, high-efficiency LEDs, and possibly a silicon-based laser.

Explore further: Black silicon can take efficiency of solar cells to new levels

More information: Batu Ghosh and Naoto Shirahata: "Colloidal silicon quantum dots: synthesis and luminescence tuning from the near-UV to the near-IR range." Sci. Technol. Adv. Mater. Vol. 15 (2014) p. 014207. dx.doi.org/10.1088/1468-6996/15/1/014207 . Article published on 17 January 2014

Related Stories

Light from silicon nanocrystal LEDs

February 18, 2013

(Phys.org)—Silicon nanocrystals have a size of a few nanometers and possess a high luminous potential. Scientists of KIT and the University of Toronto/Canada have now succeeded in manufacturing silicon-based light-emitting ...

Making silicon devices responsive to infrared light

January 6, 2014

Researchers have tried a variety of methods to develop detectors that are responsive to a broad range of infrared light—which could form imaging arrays for security systems, or solar cells that harness a broader range of ...

Novel quantum dot laser paves the way for lower-cost photonics

March 3, 2014

With the explosive growth of bandwidth demand in telecommunications networks, experts are continually seeking new ways to transmit increasingly large amounts of data in the quickest and cheapest ways possible. Photonic devices—which ...

Photonics: Enabling next-generation wireless networks

March 12, 2014

Wireless transmission at microwave frequencies is important for high-data-rate transmission applications, such as mobile phone networks, satellite links and remote imaging. Now, Xianshu Luo and colleagues from the A*STAR ...

Recommended for you

Meet the high-performance single-molecule diode

July 29, 2015

A team of researchers from Berkeley Lab and Columbia University has passed a major milestone in molecular electronics with the creation of the world's highest-performance single-molecule diode. Working at Berkeley Lab's Molecular ...

Better together: graphene-nanotube hybrid switches

August 2, 2015

Graphene has been called a wonder material, capable of performing great and unusual material acrobatics. Boron nitride nanotubes are no slackers in the materials realm either, and can be engineered for physical and biological ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.