Nanotechnology Now

Our NanoNews Digest Sponsors

Heifer International

Wikipedia Affiliate Button

Home > Press > 'Nanospears' could lead to better solar cells, lasers, lighting

These red zinc oxide "nanospears" developed by Missouri S&T researchers grow on a surface of silicon. (Illustration provided by Dr. Jay A. Switzer.)
These red zinc oxide "nanospears" developed by Missouri S&T researchers grow on a surface of silicon. (Illustration provided by Dr. Jay A. Switzer.)

Abstract:
Growing - and precisely aligning - microscopic, spear-shaped zinc oxide crystals on a surface of single-crystal silicon, researchers at Missouri University of Science and Technology may have developed a method to make more efficient solar cells.

'Nanospears' could lead to better solar cells, lasers, lighting

Rolla, MO | Posted on August 15th, 2009

Dr. Jay A. Switzer and his colleagues at Missouri S&T report in the journal Chemistry of Materials that their simple, inexpensive process could also lead to new materials for ultraviolet lasers, solid-state lighting and piezoelectric devices.

"It's kind of like growing rock candy crystals on a string," says Switzer, the Donald L. Castleman/Foundation for Chemical Research Professor of Discovery at Missouri S&T. But instead of using sugar water and string, Switzer's team grows the zinc oxide "nanospears" on the single-crystal silicon placed in a beaker filled with an alkaline solution saturated with zinc ions. The process yields tilted, single-crystal, spear-shaped rods that grow out of the silicon surface, like tiny spikes.

The spears are about 100-200 nanometers in diameter - hundreds of times smaller than the width of a human hair - and about 1 micrometer in length. A nanometer - visible only with the aid of a high-power electron microscope - is one billionth of a meter, and some nanomaterials are only a few atoms in size.

The research is reported today (Tuesday, Aug. 11) in Chemistry of Materials' online ASAP ("as soon as publishable") section and will appear in an upcoming issue.

Zinc oxide is a semiconductor that possesses some unusual physical properties, Switzer says. The material both absorbs and emits light, so it could be used in solar cells to absorb sunshine as well as in lasers or solid-state lighting as an emitter of light.

Silicon is also a semiconductor, but it absorbs light at a different part of the spectrum than zinc oxide. By growing zinc oxide on top of the silicon, "you're putting two semiconductors on top of each other," thereby widening the spectrum from which a solar cell could draw light, Switzer says.

"You can absorb more light and possibly get more power out" with a zinc oxide-silicon solar cell, he says.

Previous efforts to grow zinc oxide on silicon have been limited to expensive ultra-high-vacuum methods, and because of silicon's high reactivity, it's been impossible to deposit the zinc oxide directly, without the use of a third material as a buffer. In addition, previous attempts to align the two materials epitaxially - or perfectly one on top of the other - have been unsuccessful until now. By tilting the nanospears 51 degrees, Switzer and his team have reduced the mismatch from 40 percent to just 0.2 percent, a near-perfect alignment.

Epitaxially aligning the zinc oxide and silicon is important to ensure higher efficiency, Switzer says.

Switzer's research is supported through a four-year, $700,000 grant from the Department of Energy's Office of Basic Energy Sciences, Materials Sciences and Engineering Division.

Switzer's co-authors for the Chemistry of Materials paper are Guojun Mu and Rakesh V. Gudavarthy, both graduate students in the Chemistry Department at Missouri S&T, and Dr. Elizabeth A. Kulp, a postdoctoral associate at Missouri S&T.

####

About Missouri University of Science and Technology
Founded in 1870 as one of the first technological schools west of the Mississippi, Missouri S&T today stands poised to meet the challenges of a global, green economy.

Our name may be new, but our commitment to technological education is unchanging. As a land-grant and space-grant institution, we produced the engineers, scientists and innovators who helped drive the Industrial Revolution and propel the Space Age.

For more information, please click here

Contacts:
Office of Public Relations
1201 N. State St.
105 Campus Support Facility
Rolla, MO 65409-0220
Phone: 573-341-4328
Fax: 573-341-6157

Copyright © Missouri University of Science and Technology

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

Searching for errors in the quantum world September 21st, 2018

Viral RNA sensing: Optical detection of picomolar concentrations of RNA using switches in plasmonic chirality September 21st, 2018

UT engineers develop first method for controlling nanomotors: Breakthrough for nanotechnology as UT engineers develop first method for switching the mechanical motion of nanomotors September 21st, 2018

Nanobiotix: Update on Head and Neck Phase I/II Trial with NBTXR3 and Other program data presented at ImmunoRad 2018 September 20th, 2018

Possible Futures

Searching for errors in the quantum world September 21st, 2018

Viral RNA sensing: Optical detection of picomolar concentrations of RNA using switches in plasmonic chirality September 21st, 2018

UT engineers develop first method for controlling nanomotors: Breakthrough for nanotechnology as UT engineers develop first method for switching the mechanical motion of nanomotors September 21st, 2018

Leti Announces EU Project to Develop Powerful, Inexpensive Sensors with Photonic Integrated Circuits: REDFINCH Members Initially Targeting Applications for Gas Detection and Analysis For Refineries & Petrochemical Industry and Protein Analysis for Dairy Industry September 19th, 2018

Discoveries

Searching for errors in the quantum world September 21st, 2018

Viral RNA sensing: Optical detection of picomolar concentrations of RNA using switches in plasmonic chirality September 21st, 2018

UT engineers develop first method for controlling nanomotors: Breakthrough for nanotechnology as UT engineers develop first method for switching the mechanical motion of nanomotors September 21st, 2018

NUS researchers invent new test kit for quick, accurate and low-cost screening of diseases: Test results are denoted by a color change and could be further analyzed by a smartphone app, making it attractive as a point-of-care diagnostic device September 19th, 2018

Announcements

Searching for errors in the quantum world September 21st, 2018

Viral RNA sensing: Optical detection of picomolar concentrations of RNA using switches in plasmonic chirality September 21st, 2018

UT engineers develop first method for controlling nanomotors: Breakthrough for nanotechnology as UT engineers develop first method for switching the mechanical motion of nanomotors September 21st, 2018

Nanobiotix: Update on Head and Neck Phase I/II Trial with NBTXR3 and Other program data presented at ImmunoRad 2018 September 20th, 2018

Energy

Leti Announces EU Project to Develop Powerful, Inexpensive Sensors with Photonic Integrated Circuits: REDFINCH Members Initially Targeting Applications for Gas Detection and Analysis For Refineries & Petrochemical Industry and Protein Analysis for Dairy Industry September 19th, 2018

S, N co-doped carbon nanotube-encapsulated CoS2@Co: Efficient and stable catalysts for water splitting September 10th, 2018

September 5th, 2018

Rice U. lab probes molecular limit of plasmonics: Optical effect detailed in organic molecules with fewer than 50 atoms September 5th, 2018

Grants/Sponsored Research/Awards/Scholarships/Gifts/Contests/Honors/Records

UT engineers develop first method for controlling nanomotors: Breakthrough for nanotechnology as UT engineers develop first method for switching the mechanical motion of nanomotors September 21st, 2018

Halas wins American Chemical Society Award in Colloid Chemistry: Rice University nanophotonics pioneer honored for colloid research September 18th, 2018

New photonic chip promises more robust quantum computers September 14th, 2018

A Comprehensive Guide: The Future of Nanotechnology September 13th, 2018

Solar/Photovoltaic

September 5th, 2018

NUST MISIS scientists present metamaterial for solar cells and nanooptics July 23rd, 2018

Northwestern researchers achieve unprecedented control of polymer grids: Materials could find applications in water purification, solar energy storage, body armor June 22nd, 2018

Team achieves two-electron chemical reactions using light energy, gold May 15th, 2018

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



  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More











ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project