News


Carbon nanotubes improve solar cell performance

3 September 2008 News

Nanotechnology has paved the way for the introduction or activation of unique characteristics in materials, by enhancing their physical and chemical properties.

This core principle has been applied to carbon nanotubes (CNTs) by introducing defects that result in improved performance and optimised characteristics needed in other materials.

CNTs offer properties such as electrical conductivity, chemical stability, high surface area, and optoelectronic properties that find applications in energy and storage technologies.

To study the effect of introducing CNTs in dye-sensitised solar cells (DSSC), researchers from Columbia University and Michigan State University have collaborated to replace the conventional platinum cathode in DSSCs with CNTs.

DSSCs are a low-cost solar energy technology consisting of a photosensitive dye that absorbs photons from the sun and converts them to electrical charges which diffuse across the electrolyte to form an electric current. Prior research has resulted in using platinum deposited over transparent conducting oxide (TCO) as a cathode in DSSC to achieve high efficiency cells. However, the degradation of platinum over time poses a significant challenge in identifying the right material to maintain efficiency and operation over time. In this regard, the high conductivity and transparency of CNTs make them a potentially attractive option.

The research was aimed at identifying the responses of catalytic strength, transparency and sheet resistance of CNT films. The researchers deposited CNT films on a conducting substrate inside the cells and then monitored the electrochemical activity. They did this by using electrochemical impedance spectroscopy (EIS) of the charge-transfer resistance associated as a function of film transparency and loading. The films were then exposed to ultraviolet-generated ozone, resulting in a dramatic increase of catalytic activity.

This increase was attributed to defects that were introduced by the treatment with ozone. The defects appeared as pits that acted as sites for the chemical reaction, resulting in an increase of the reaction rate by more than 10 times. Conductivity and transparency was measured by varying and depositing CNTs of different sizes on substrates and incorporating them into the cells. This indicated that long nanotubes displayed higher and better conductivity and transparency.

“It shows that carbon nanotubes can be extremely effective catalysts,” said head researcher Jessica Trancik. “It also demonstrates a way in which nanostructuring materials can be used to shift tradeoffs between multiple properties, in order to make inexpensive materials behave in advanced ways. This is critical for the development of climate friendly energy technologies.”

The researchers anticipate the application of this research in DSSCs as well as possibly in batteries, fuel cells, sensors and other electroanalytical devices. The researchers believe that CNTs offer high flexibility and are less prone to cracking than TCO. This would make DSSCs easy to manufacture by roll-to-roll processing and integrate into various configurations.

For more information contact Patrick Cairns, Frost & Sullivan, +27 (0)21 680 3274, [email protected], www.frost.com





Share this article:
Share via emailShare via LinkedInPrint this page

Further reading:

Electronic News Digest
News
A brief synopsis of current global news relating to the electronic engineering fields with regards to company finances, general company news, and engineering technologies.

Read more...
Jemstech to produce PCB assemblies for Kamstrup
Jemstech News
Jemstech is pleased to announce that they have successfully concluded a supplier agreement with Kamstrup A/S in Denmark, a leading supplier of intelligent metering solutions in the global market.

Read more...
New appointments at Hiconnex
Hiconnex News
Hiconnex, a leading provider of electronic components and solutions, has announced key appointments to support its continued growth and commitments to its clients.

Read more...
FoundriesFactory service more affordable for smaller OEMs
News
Foundries.io has announced a new, tiered pricing scheme which reduces the cost of its highly regarded FoundriesFactory service for OEMs in the development phase of a new edge AI or Linux OS-based product.

Read more...
DMASS 2024 results
News
The semiconductor business faced a severe downturn, with a 31,9% decrease compared to 2023 and a 30,3% drop in Q4 2024 compared to the same period last year.

Read more...
Using satellite comms to end copper theft
News
According to Transnet COO Solly Letsoalo, the scourge of copper theft could be a thing of the past by eliminating the use of copper cabling and switching to a satellite communication system.

Read more...
Strategic merger: Etion Create and Nanoteq
Etion Create News
Reunert has announced the successful merger of two business units within the Applied Electronics Segment, namely Etion Create and Nanoteq, effective 1 October 2024.

Read more...
Securex South Africa 2025
Specialised Exhibitions News
Securex South Africa 2025 is co-located with A-OSH EXPO, Facilities Management Expo, and Firexpo to provide a time-saver for visitors looking for holistic solutions for their facilities.

Read more...
Chinese AI causes Silicon Valley stocks to tumble
News
Many stocks took a downward spike, with Nvidia being the hardest hit, losing 16,9% after one day’s trading.

Read more...
Silicon Labs 4th quarter results
News
Silicon Labs has reported financial results for the fourth quarter with highlights including a total revenue of $166 million and Home & Life revenue up 11% to $78 million.

Read more...