Nanotechnology Now

Our NanoNews Digest Sponsors





Heifer International

Wikipedia Affiliate Button


DHgate

Home > Press > NUS scientists use low cost technique to improve properties and functions of nanomaterials: By 'drawing' micropatterns on nanomaterials using a focused laser beam, scientists could modify properties of nanomaterials for effective applications in photonic and optoelectric applicat

Mesoporous silicon nanowires were scanned by a focused laser beam in two different patterns, imaged by bright-field optical microscope, as depicted by (a) and (c), as well as fluorescence microscopy, as depicted by (b) and (d). Evidently, the images hidden in boxes shown in (a) and (c) are clearly revealed under fluorescence microscopy.

Credit: National University of Singapore
Mesoporous silicon nanowires were scanned by a focused laser beam in two different patterns, imaged by bright-field optical microscope, as depicted by (a) and (c), as well as fluorescence microscopy, as depicted by (b) and (d). Evidently, the images hidden in boxes shown in (a) and (c) are clearly revealed under fluorescence microscopy.

Credit: National University of Singapore

Abstract:
The challenges faced by researchers in modifying properties of nanomaterials for application in devices may be addressed by a simple technique, thanks to recent innovative studies conducted by scientists from the National University of Singapore (NUS).

NUS scientists use low cost technique to improve properties and functions of nanomaterials: By 'drawing' micropatterns on nanomaterials using a focused laser beam, scientists could modify properties of nanomaterials for effective applications in photonic and optoelectric applicat

Singapore | Posted on July 22nd, 2014

Through the use of a simple, efficient and low cost technique involving a focused laser beam, two NUS research teams, led by Professor Sow Chorng Haur from the Department of Physics at the NUS Faculty of Science, demonstrated that the properties of two different types of materials can be controlled and modified, and consequently, their functionalities can be enhanced.

Said Prof Sow, "In our childhood, most of us are likely to have the experience of bringing a magnifying glass outdoors on a sunny day and tried to focus sunlight onto a piece of paper to burn the paper. Such a simple approach turns out to be a very versatile tool in research. Instead of focusing sunlight, we can focus laser beam onto a wide variety of nanomaterials and study effects of the focused laser beam has on these materials."

Micropatterns 'drawn' on MoS2 films could enhance electrical conductivity and photoconductivity

Molybdenum disulfide (MoS2), a class of transition metal dichalcogenide compound, has attracted great attention as an emerging two-dimensional (2D) material due to wide recognition of its potential in and optoelectronics. One of the many fascinating properties of 2D MoS2 film is that its properties depend on the thickness of the film. In addition, its properties can be modified once the film is modified chemically. Hence one of the challenges in this field is the ability to create microdevices out of the MoS2 film comprising components with different thickness or chemical nature.

To address this technological challenge, Prof Sow, Dr Lu Junpeng, a postdoctoral candidate from the Department of Physics at the NUS Faculty of Science, as well as their team members, utilised an optical microscope-focused laser beam setup to 'draw' micropatterns directly onto large area MoS2 films as well as to thin the films.

With this simple and low cost approach, the scientists were able to use the focused laser beam to selectively 'draw' patterns onto any region of the film to modify properties of the desired area, unlike other current methods where the entire film is modified.

Interestingly, they also found that the electrical conductivity and photoconductivity of the modified material had increased by more than 10 times and about five times respectively. The research team fabricated a photodetector using laser modified MoS2 film and demonstrated the superior performance of MoS2 for such application.

This innovation was first published online in the journal ACS Nano on 24 May 2014.

Hidden images 'drawn' by focused laser beam on silicon nanowires could improve optical functionalities

In a related study published in the journal Scientific Reports on 13 May 2014, Prof Sow led another team of researchers from the NUS Faculty of Science, in collaboration with scientists from Hong Kong Baptist University, to investigate how 'drawing' micropatterns on mesoporous silicon nanowires could change the properties of nanowires and advance their applications.

The team scanned a focused laser beam rapidly onto an array of mesoporous silicon nanowires, which are closely packed like the tightly woven threads of a carpet. They found that the focused laser beam could modify the optical properties of the nanowires, causing them to emit greenish-blue fluorescence light. This is the first observation of such a laser-modified behaviour from the mesoporous silicon nanowires to be reported.

The researchers systematically studied the laser-induced modification to gain insights into establishing control over the optical properties of the mesoporous silicon nanowires. Their understanding enabled them to 'draw' a wide variety of micropatterns with different optical functionalities using the focused laser beam.

To put their findings to the test, the researchers engineered the functional components of the nanowires with interesting applications. The research team demonstrated that the micropatterns created at a low laser power are invisible under bright-field optical microscope, but become apparent under fluorescence microscope, indicating the feasibility of hidden images.

Further research

The fast growing field of electronics and optoelectronics demands precise material deposition with application-specific optical, electrical, chemical, and mechanical properties.

To develop materials with properties that can cater to the industry's demands, Prof Sow, together with his team of researchers, will extend the versatile focused laser beam technique to more nanomaterials. In addition, they will look into further improving the properties of MoS2 and mesoporous silicon with different techniques.

####

For more information, please click here

Contacts:
Carolyn Fong

65-651-65399

Copyright © National University of Singapore

If you have a comment, please Contact us.

Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.

Bookmark:
Delicious Digg Newsvine Google Yahoo Reddit Magnoliacom Furl Facebook

Related News Press

News and information

Multi-million pound project to use nanotechnology to improve safety September 4th, 2015

Magnetic wormhole connecting 2 regions of space created for the first time: The device could have applications in medicine, opening up ways to make MRIs more comfortable for patients September 4th, 2015

Tongfang Global and QD Vision Partner to Bring Wide Color Gamut to Global Television Lines: Color IQTM quantum dots help boost company’s focus on superior color reproduction September 3rd, 2015

QEOS and GLOBALFOUNDRIES to Offer Industry’s First CMOS Platform for MillimeterWave Markets: GLOBALSOLUTIONSSM Partnership will enable next-generation wireless technologies for applications in IoT, 5G and automotive September 3rd, 2015

Chip Technology

GLOBALFOUNDRIES and Catena Partner to Provide Next-Generation RF Connectivity Solutions for Growing Wireless Markets: Catena Wi-Fi and Bluetooth RF technologies available on GLOBALFOUNDRIES 28nm Super Low Power Process technology September 3rd, 2015

For 2-D boron, it's all about that base: Rice University theorists show flat boron form would depend on metal substrates September 2nd, 2015

Phagraphene, a 'relative' of graphene, discovered September 2nd, 2015

Nanometrics to Participate in the Citi 2015 Global Technology Conference August 26th, 2015

Optical computing/ Photonic computing

Quantum diffraction at a breath of nothing: Physicists build stable diffraction structure in atomically thin graphene August 25th, 2015

A little light interaction leaves quantum physicists beaming August 25th, 2015

'Magic' sphere for information transfer: Professor at the Lomonosov Moscow State University made the «magic» sphere for information transfer August 24th, 2015

High-precision control of nanoparticles for digital applications August 19th, 2015

Discoveries

Magnetic wormhole connecting 2 regions of space created for the first time: The device could have applications in medicine, opening up ways to make MRIs more comfortable for patients September 4th, 2015

QEOS and GLOBALFOUNDRIES to Offer Industry’s First CMOS Platform for MillimeterWave Markets: GLOBALSOLUTIONSSM Partnership will enable next-generation wireless technologies for applications in IoT, 5G and automotive September 3rd, 2015

Making nanowires from protein and DNA September 3rd, 2015

Making fuel from light: Argonne research sheds light on photosynthesis and creation of solar fuel September 3rd, 2015

Materials/Metamaterials

Magnetic wormhole connecting 2 regions of space created for the first time: The device could have applications in medicine, opening up ways to make MRIs more comfortable for patients September 4th, 2015

Sustainable nanotechnology center September 1st, 2015

Using ultrathin sheets to discover new class of wrapped shapes: UMass Amherst materials researchers describe a new regime of wrapped shapes August 31st, 2015

An engineered surface unsticks sticky water droplets August 31st, 2015

Announcements

Multi-million pound project to use nanotechnology to improve safety September 4th, 2015

Magnetic wormhole connecting 2 regions of space created for the first time: The device could have applications in medicine, opening up ways to make MRIs more comfortable for patients September 4th, 2015

Making nanowires from protein and DNA September 3rd, 2015

Making fuel from light: Argonne research sheds light on photosynthesis and creation of solar fuel September 3rd, 2015

Interviews/Book Reviews/Essays/Reports/Podcasts/Journals/White papers

Magnetic wormhole connecting 2 regions of space created for the first time: The device could have applications in medicine, opening up ways to make MRIs more comfortable for patients September 4th, 2015

Making nanowires from protein and DNA September 3rd, 2015

Making fuel from light: Argonne research sheds light on photosynthesis and creation of solar fuel September 3rd, 2015

Reversible Writing with Light: Self-assembling nanoparticles take their cues from their surroundings September 3rd, 2015

Photonics/Optics/Lasers

Reversible Writing with Light: Self-assembling nanoparticles take their cues from their surroundings September 3rd, 2015

A marine creature's magic trick explained: Crystal structures on the sea sapphire's back appear differently depending on the angle of reflection September 2nd, 2015

Scientists 'squeeze' light one particle at a time: A team of scientists have measured a bizarre effect in quantum physics, in which individual particles of light are said to have been 'squeezed' -- an achievement which at least one textbook had written off as hopeless September 1st, 2015

Nanotechnology that will impact the Security & Defense sectors to be discussed at NanoSD2015 conference August 25th, 2015

NanoNews-Digest
The latest news from around the world, FREE



  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoTech-Transfer
University Technology Transfer & Patents
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More











ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project







Car Brands
Buy website traffic