Featured Research

from universities, journals, and other organizations

Nanotube electrodes improve solar cells

Date:
April 17, 2012
Source:
Rice University
Summary:
Forests of carbon nanotubes are an efficient alternative for platinum electrodes in dye-sensitized solar cells, according to new research.

A dye-sensitized solar cell developed at Rice University and Tsinghua University replaces platinum with carbon nanotubes and iodine electrolyte with a sulfide-based electrolyte. The researchers hope to make dye-sensitized solar cells better and cheaper.
Credit: Jeff Fitlow/Rice University

Forests of carbon nanotubes are an efficient alternative for platinum electrodes in dye-sensitized solar cells (DSC), according to new research by collaborators at Rice University and Tsinghua University.

The single-wall nanotube arrays, grown in a process invented at Rice, are both much more electroactive and potentially cheaper than platinum, a common catalyst in DSCs, said Jun Lou, a materials scientist at Rice. In combination with newly developed sulfide electrolytes synthesized at Tsinghua, they could lead to more efficient and robust solar cells at a fraction of the current cost for traditional silicon-based solar cells.

Lou and co-lead investigator Hong Lin, a professor of materials science and engineering at Tsinghua, detailed their work in the online, open-access Nature journal Scientific Reports this week.

DSCs are easier to manufacture than silicon-based solid-state photovoltaic cells but not as efficient, said Lou, a professor of mechanical engineering and materials science. "DSCs are sensitized with dyes, ideally organic dyes like the juices from berries -- which some students have actually used in demonstrations."

Dyes absorb photons from sunlight and generate a charge in the form of electrons, which are captured first by a semiconducting titanium oxide layer deposited on a current collector before flowing back to the counter electrode through another current collector. Progress has been made in the manufacture of DSCs that incorporate an iodine-based electrolyte, but iodine tends to corrode metallic current collectors, which "poses a challenge for its long-termreliability," Lou said.

Iodine electrolyte also has the unfortunate tendency to absorb light in the visible wavelengths, "which means fewer photons could be utilized," Lou said.

So Tsinghua researchers decided to try a noncorrosive, sulfide-based electrolyte that absorbs little visible light and works well with the single-walled carbon nanotube carpets created in the Rice lab of Robert Hauge, a co-author of the paper and a distinguished faculty fellow in chemistry at Rice's Richard E. Smalley Institute for Nanoscale Science and Technology .

"These are very versatile materials," Lou said. "Single-walled carbon nanotubes have been around at Rice for a very long time, and people have found many different ways to use them. This is another way that turns out to be very well-matched to a sulfid-based electrolyte in DSC technology."

Both Rice and Tsinghua built working solar cells, with similar results. They were able to achieve a power conversion efficiency of 5.25 percent -- lower than the DSC record of 11 percent with iodine electrolytes a platinum electrode, but significantly higher a control that combined the new electrolyte with a traditional platinum counter electrode. Resistance between the new electrolyte and counter electrode is "the lowest we've ever seen," Lou said.

There's much work to be done, however. "The carbon nanotube-to-current collector still has a pretty large contact resistance, and the effects of structuraldefects in carbon nanotubes on their corresponding performance are not fully understood, but we believe once we optimize everything, we're going to get decent efficiency and make the whole thing very affordable," Lou said. "The real attraction is that it will be a very low-cost alternative to silicon-based solar cells."

Pei Dong, a graduate student in Lou's lab, and Feng Hao, a graduate student at Tsinghua, are lead authors of the paper. Co-authors include Rice graduate students Jing Zhang and Philip Loya, Yongchang Zhang of Tsinghua and Professor Jianbao Li of Hainan University, China.

The project was supported by tNational High Technology Research and Development Program of China, the Welch Foundation and the Faculty Initiative Fund at Rice.


Story Source:

The above story is based on materials provided by Rice University. Note: Materials may be edited for content and length.


Journal Reference:

  1. Feng Hao, Pei Dong, Jing Zhang, Yongchang Zhang, Phillip E. Loya, Robert H. Hauge, Jianbao Li, Jun Lou, Hong Lin. High Electrocatalytic Activity of Vertically Aligned Single-Walled Carbon Nanotubes towards Sulfide Redox Shuttles. Scientific Reports, 2012; 2 DOI: 10.1038/srep00368

Cite This Page:

Rice University. "Nanotube electrodes improve solar cells." ScienceDaily. ScienceDaily, 17 April 2012. <www.sciencedaily.com/releases/2012/04/120417125627.htm>.
Rice University. (2012, April 17). Nanotube electrodes improve solar cells. ScienceDaily. Retrieved July 31, 2014 from www.sciencedaily.com/releases/2012/04/120417125627.htm
Rice University. "Nanotube electrodes improve solar cells." ScienceDaily. www.sciencedaily.com/releases/2012/04/120417125627.htm (accessed July 31, 2014).

Share This




More Matter & Energy News

Thursday, July 31, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Britain Testing Driverless Cars on Roadways

Britain Testing Driverless Cars on Roadways

AP (July 30, 2014) British officials said on Wednesday that driverless cars will be tested on roads in as many as three cities in a trial program set to begin in January. Officials said the tests will last up to three years. (July 30) Video provided by AP
Powered by NewsLook.com
Amid Drought, UCLA Sees Only Water

Amid Drought, UCLA Sees Only Water

AP (July 30, 2014) A ruptured 93-year-old water main left the UCLA campus awash in 8 million gallons of water in the middle of California's worst drought in decades. (July 30) Video provided by AP
Powered by NewsLook.com
Smartphone Powered Paper Plane Debuts at Airshow

Smartphone Powered Paper Plane Debuts at Airshow

AP (July 30, 2014) Smartphone powered paper airplane that was popular on crowdfunding website KickStarter makes its debut at Wisconsin airshow (July 30) Video provided by AP
Powered by NewsLook.com
U.K. To Allow Driverless Cars On Public Roads

U.K. To Allow Driverless Cars On Public Roads

Newsy (July 30, 2014) Driverless cars could soon become a staple on U.K. city streets, as they're set to be introduced to a few cities in 2015. Video provided by Newsy
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