Featured Research

from universities, journals, and other organizations

Bringing down the cost of microbial fuel cells

Date:
June 23, 2012
Source:
University of Wisconsin - Milwaukee
Summary:
A new catalyst material could dramatically reduce the cost of producing microbial fuel cells.

Zhen (Jason) He, assistant professor of mechanical engineering (left), and Junhong Chen, professor of mechanical engineering, display a strip of carbon that contains the novel nanorod catalyst material they developed for microbial fuel cells.
Credit: Photo by Troye Fox

Engineers at the University of Wisconsin-Milwaukee (UWM) have identified a catalyst that provides the same level of efficiency in microbial fuel cells (MFCs) as the currently used platinum catalyst, but at 5% of the cost.

Since more than 60% of the investment in making microbial fuel cells is the cost of platinum, the discovery may lead to much more affordable energy conversion and storage devices.

The material -- nitrogen-enriched iron-carbon nanorods -- also has the potential to replace the platinum catalyst used in hydrogen-producing microbial electrolysis cells (MECs), which use organic matter to generate a possible alternative to fossil fuels.

"Fuel cells are capable of directly converting fuel into electricity," says UWM Professor Junhong Chen, who created the nanorods and is testing them with Assistant Professor Zhen (Jason) He. "With fuel cells, electrical power from renewable energy sources can be delivered where and when required, cleanly, efficiently and sustainably."

The scientists also found that the nanorod catalyst outperformed a graphene-based alternative being developed elsewhere. In fact, the pair tested the material against two other contenders to replace platinum and found the nanorods' performance consistently superior over a six-month period.

The nanorods have been proved stable and are scalable, says Chen, but more investigation is needed to determine how easily they can be mass-produced. More study is also required to determine the exact interaction responsible for the nanorods' performance.

The work was published in March in the journal Advanced Materials.

The right recipe

MFCs generate electricity while removing organic contaminants from wastewater. On the anode electrode of an MFC, colonies of bacteria feed on organic matter, releasing electrons that create a current as they break down the waste.

On the cathode side, the most important reaction in MFCs is the oxygen reduction reaction (ORR). Platinum speeds this slow reaction, increasing efficiency of the cell, but it is expensive.

Microbial electrolysis cells (MECs) are related to MFCs. However, instead of electricity, MECs produce hydrogen. In addition to harnessing microorganisms at the anode, MECS also use decomposition of organic matter and platinum in a catalytic process at their cathodes.

Chen and He's nanorods incorporate the best characteristics of other reactive materials, with nitrogen attached to the surface of the carbon rod and a core of iron carbide. Nitrogen's effectiveness at improving the carbon catalyst is already well known. Iron carbide, also known for its catalytic capabilities, interacts with the carbon on the rod surface, providing "communication" with the core. Also, the material's unique structure is optimal for electron transport, which is necessary for ORR.

When the nanorods were tested for potential use in MECs, the material did a better job than the graphene-based catalyst material, but it was still not as efficient as platinum.

"But it shows that there could be more diverse applications for this material, compared to graphene," says He. "And it gave us clues for why the nanorods performed differently in MECs."

Research with MECs was published in June in the journal Nano Energy.


Story Source:

The above story is based on materials provided by University of Wisconsin - Milwaukee. The original article was written by Laura L. Hunt. Note: Materials may be edited for content and length.


Journal References:

  1. Zhenhai Wen, Suqin Ci, Fei Zhang, Xinliang Feng, Shumao Cui, Shun Mao, Shenglian Luo, Zhen He, Junhong Chen. Nitrogen-Enriched Core-Shell Structured Fe/Fe3C-C Nanorods as Advanced Electrocatalysts for Oxygen Reduction Reaction (Adv. Mater. 11/2012). Advanced Materials, 2012; 24 (11): 1398 DOI: 10.1002/adma.201290061
  2. Li Xiao, Zhenhai Wen, Suqin Ci, Junhong Chen, Zhen He. Carbon/iron-based nanorod catalysts for hydrogen production in microbial electrolysis cells. Nano Energy, 2012; DOI: 10.1016/j.nanoen.2012.06.002

Cite This Page:

University of Wisconsin - Milwaukee. "Bringing down the cost of microbial fuel cells." ScienceDaily. ScienceDaily, 23 June 2012. <www.sciencedaily.com/releases/2012/06/120623094430.htm>.
University of Wisconsin - Milwaukee. (2012, June 23). Bringing down the cost of microbial fuel cells. ScienceDaily. Retrieved July 28, 2014 from www.sciencedaily.com/releases/2012/06/120623094430.htm
University of Wisconsin - Milwaukee. "Bringing down the cost of microbial fuel cells." ScienceDaily. www.sciencedaily.com/releases/2012/06/120623094430.htm (accessed July 28, 2014).

Share This




More Earth & Climate News

Monday, July 28, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Raw: Sea Turtle Hatchlings Emerge from Nest

Raw: Sea Turtle Hatchlings Emerge from Nest

AP (July 27, 2014) A live-streaming webcam catches loggerhead sea turtle hatchlings emerging from a nest in the Florida Keys. (July 27) Video provided by AP
Powered by NewsLook.com
Trees Could Save More Than 850 Lives Each Year

Trees Could Save More Than 850 Lives Each Year

Newsy (July 27, 2014) A national study conducted by the USDA Forest Service found that trees collectively save more than 850 lives on an annual basis. Video provided by Newsy
Powered by NewsLook.com
Phoenix Thunderstorm Creates Giant Wall of Dust

Phoenix Thunderstorm Creates Giant Wall of Dust

Reuters - US Online Video (July 26, 2014) A giant wall of dust slowly moves north over the Phoenix area after a summer monsoon thunderstorm. Mana Rabiee reports. Video provided by Reuters
Powered by NewsLook.com
Rare Lemur Among Baby Animals Debuted at Cleveland Zoo

Rare Lemur Among Baby Animals Debuted at Cleveland Zoo

Reuters - US Online Video (July 26, 2014) A rare baby Lemur is among several baby animals getting their public debut at a Cleveland zoo. Mana Rabiee reports. Video provided by Reuters
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