Featured Research

from universities, journals, and other organizations

Butterfly wings' 'art of blackness' could boost production of green fuels

Date:
March 26, 2012
Source:
American Chemical Society (ACS)
Summary:
Butterfly wings may rank among the most delicate structures in nature, but they have given researchers powerful inspiration for new technology that doubles production of hydrogen gas — a green fuel of the future — from water and sunlight.

Nanostructures on butterfly wings make them extremely black and help researchers collect sunlight to make hydrogen gas from water.
Credit: American Chemical Society

Butterfly wings may rank among the most delicate structures in nature, but they have given researchers powerful inspiration for new technology that doubles production of hydrogen gas -- a green fuel of the future -- from water and sunlight.

The researchers presented their findings in San Diego on March 26 at the American Chemical Society's (ACS') 243rd National Meeting & Exposition.

Tongxiang Fan, Ph.D., who reported on the use of two swallowtail butterflies -- Troides aeacus (Heng-chun birdwing butterfly) and Papilio helenus Linnaeus (Red Helen) -- as models, explained that finding renewable sources of energy is one of the great global challenges of the 21st century. One promising technology involves producing clean-burning hydrogen fuel from sunlight and water. It can be done in devices that use sunlight to kick up the activity of catalysts that split water into its components, hydrogen and oxygen. Better solar collectors are the key to making the technology practical, and Fan's team turned to butterfly wings in their search for making solar collectors that gather more useful light.

"We realized that the solution to this problem may have been in existence for millions of years, fluttering right in front of our eyes," Fan said. "And that was correct. Black butterfly wings turned out to be a natural solar collector worth studying and mimicking," Fan said.

Scientists long have known that butterfly wings contain tiny scales that serve as natural solar collectors to enable butterflies, which cannot generate enough heat from their own metabolism, to remain active in the cold. When butterflies spread their wings and bask in the sun, those solar collectors are soaking up sunlight and warming the butterfly's body.

Fan's team at Shanghai Jiao Tong University in China used an electron microscope to reveal the most-minute details of the scale architecture on the wings of black butterflies -- black being the color that absorbs the maximum amount of sunlight.

"We were searching the 'art of blackness' for the secret of how those black wings absorb so much sunlight and reflect so little," Fan explained.

Scientists initially thought it was simply a matter of the deep inky black color, due to the pigment called melanin, which also occurs in human skin. More recently, however, evidence began to emerge indicating that the structure of the scales on the wings should not be ignored.

Fan's team observed elongated rectangular scales arranged like overlapping shingles on the roof of a house. The butterflies they examined had slightly different scales, but both had ridges running the length of the scale with very small holes on either side that opened up onto an underlying layer.

The steep walls of the ridges help funnel light into the holes, Fan explained. The walls absorb longer wavelengths of light while allowing shorter wavelengths to reach a membrane below the scales. Using the images of the scales, the researchers created computer models to confirm this filtering effect. The nano-hole arrays change from wave guides for short wavelengths to barriers and absorbers for longer wavelengths, which act just like a high-pass filtering layer.

The group used actual butterfly-wing structures to collect sunlight, employing them as templates to synthesize solar-collecting materials. They chose the black wings of the Asian butterfly Papilio helenus Linnaeus, or Red Helen, and transformed them to titanium dioxide by a process known as dip-calcining. Titanium dioxide is used as a catalyst to split water molecules into hydrogen and oxygen. Fan's group paired this butterfly-wing patterned titanium dioxide with platinum nanoparticles to increase its water-splitting power. The butterfly-wing compound catalyst produced hydrogen gas from water at more than twice the rate of the unstructured compound catalyst on its own.

"These results demonstrate a new strategy for mimicking Mother Nature's elaborate creations in making materials for renewable energy. The concept of learning from nature could be extended broadly, and thus give a broad scope of building technologically unrealized hierarchical architecture and design blueprints to exploit solar energy for sustainable energy resources," he concluded.

The scientists acknowledged funding from National Natural Science Foundation of China (No.51172141 and 50972090), Shanghai Rising-star Program (No.10QH1401300).


Story Source:

The above story is based on materials provided by American Chemical Society (ACS). Note: Materials may be edited for content and length.


Cite This Page:

American Chemical Society (ACS). "Butterfly wings' 'art of blackness' could boost production of green fuels." ScienceDaily. ScienceDaily, 26 March 2012. <www.sciencedaily.com/releases/2012/03/120326160655.htm>.
American Chemical Society (ACS). (2012, March 26). Butterfly wings' 'art of blackness' could boost production of green fuels. ScienceDaily. Retrieved September 2, 2014 from www.sciencedaily.com/releases/2012/03/120326160655.htm
American Chemical Society (ACS). "Butterfly wings' 'art of blackness' could boost production of green fuels." ScienceDaily. www.sciencedaily.com/releases/2012/03/120326160655.htm (accessed September 2, 2014).

Share This




More Plants & Animals News

Tuesday, September 2, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

We've Got Mites Living In Our Faces And So Do You

We've Got Mites Living In Our Faces And So Do You

Newsy (Aug. 30, 2014) A new study suggests 100 percent of adult humans (those over 18 years of age) have Demodex mites living in their faces. Video provided by Newsy
Powered by NewsLook.com
Washington Wildlife Center Goes Nuts Over Baby Squirrels

Washington Wildlife Center Goes Nuts Over Baby Squirrels

Reuters - US Online Video (Aug. 30, 2014) An animal rescue in Washington state receives an influx of orphaned squirrels, keeping workers busy as they nurse them back to health. Rough Cut (no reporter narration). Video provided by Reuters
Powered by NewsLook.com
Experimental Ebola Drug ZMapp Cures Lab Monkeys Of Disease

Experimental Ebola Drug ZMapp Cures Lab Monkeys Of Disease

Newsy (Aug. 29, 2014) In a new study, a promising experimental treatment for Ebola managed to cure a group of infected macaque monkeys. Video provided by Newsy
Powered by NewsLook.com
Killer Amoeba Found in Louisiana Water System

Killer Amoeba Found in Louisiana Water System

AP (Aug. 28, 2014) State health officials say testing has confirmed the presence of a killer amoeba in a water system serving three St. John the Baptist Parish towns. (Aug. 28) Video provided by AP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins