Researchers demonstrate ‘avalanche effect’ in solar cells

This physical effect could pave the way for cheap, high-output solar cells. The findings are to be published in scientific journal Nano Letters this week.

Solar cells provide great opportunities for future large-scale electricity generation. However, there are currently significant limitations, such as the relatively low output of most solar cells (typically fifteen percent) and high manufacturing costs.

One possible improvement could derive from a new type of solar cell made of semiconducting nanocrystals (crystals with dimensions in the nanometre size range). In conventional solar cells, one photon (light particle) can release precisely one electron. The creation of these free electrons ensures that the solar cell works and can provide power. The more electrons released, the higher the output of the solar cell.

In some semiconducting nanocrystals, however, one photon can release two or three electrons, hence the term avalanche effect. This could theoretically lead to a maximum output of 44 percent in a solar cell comprising the correct semiconducting nanocrystals. Moreover, these solar cells can be manufactured relatively cheaply.

The avalanche effect was first measured by researchers at the Los Alamos National Laboratories in 2004. Since then, the scientific world has raised doubts about the value of these measurements. Does the avalanche effect really exist or not?

Within the Joint Solar Programme TU Delft’s Prof. Laurens Siebbeles has now demonstrated that the avalanche effect does indeed occur in lead selenide (PbSe) nanocrystals. It has been established, however, that the effect in this material is smaller than previously assumed. Siebbeles’ results are more reliable than those of other scientists thanks to more careful and more detailed measurement using ultra-fast laser methods.

Siebbeles believes that this research paves the way for further unravelling the secrets of the avalanche effect.

Media Contact

Maarten van der Sanden alfa

More Information:

http://www.tudelft.nl

All latest news from the category: Power and Electrical Engineering

This topic covers issues related to energy generation, conversion, transportation and consumption and how the industry is addressing the challenge of energy efficiency in general.

innovations-report provides in-depth and informative reports and articles on subjects ranging from wind energy, fuel cell technology, solar energy, geothermal energy, petroleum, gas, nuclear engineering, alternative energy and energy efficiency to fusion, hydrogen and superconductor technologies.

Back to home

Comments (0)

Write a comment

Newest articles

Lighting up the future

New multidisciplinary research from the University of St Andrews could lead to more efficient televisions, computer screens and lighting. Researchers at the Organic Semiconductor Centre in the School of Physics and…

Researchers crack sugarcane’s complex genetic code

Sweet success: Scientists created a highly accurate reference genome for one of the most important modern crops and found a rare example of how genes confer disease resistance in plants….

Evolution of the most powerful ocean current on Earth

The Antarctic Circumpolar Current plays an important part in global overturning circulation, the exchange of heat and CO2 between the ocean and atmosphere, and the stability of Antarctica’s ice sheets….

Partners & Sponsors