advertisement
Science News
from research organizations

Solar fuels: better efficiency using microwires

Date:
January 15, 2018
Source:
University of Twente
Summary:
Researchers have made significant efficiency improvements to the technology used to generate solar fuels. This involves the direct conversion of energy from sunlight into a usable fuel (in this case, hydrogen). Using only earth-abundant materials, they developed the most efficient conversion method to date. The trick was to decouple the site where sunlight is captured from the site where the conversion reaction takes place.
Share:
FULL STORY

Researchers at the University of Twente's MESA+ Institute for Nanotechnology have made significant efficiency improvements to the technology used to generate solar fuels. This involves the direct conversion of energy from sunlight into a usable fuel (in this case, hydrogen). Using only earth-abundant materials, they developed the most efficient conversion method to date. The trick was to decouple the site where sunlight is captured from the site where the conversion reaction takes place. This study was published today in the journal Nature Energy.

Researchers around the world are working on the development of solar fuel technology. This involves generating sustainable fuels using only sunlight, CO2 and water, the basic ingredients used by plants. A group of researchers from the University of Twente's MESA+ research institute are working on a solar-to-fuel device that produces hydrogen. They have now achieved a major breakthrough in this area of fundamental research. Using earth-abundant materials (i.e. avoiding the use of scarce and expensive precious metals), they have developed the most efficient method to date for converting light into hydrogen. The system consists of silicon microwires less than one tenth of a millimetre long, the tops of which are coated with a catalyst. The photons (light particles) are collected between the microwires. The chemical reaction in which hydrogen is formed takes place on the catalyst at the tips of the microwires.

Decoupling

By varying the density and length of the microwires, the researchers ultimately achieved a maximum efficiency of 10.8 percent. They managed to achieve this by decoupling the site where the photons are collected from the site where the conversion reaction takes place. This is necessary because catalysts usually reflect light. Yet -- to make the conversion as efficient as possible -- you want them to absorb as much light as possible. It is important to achieve this decoupling at the microscale, because at larger scales the conductivity of the silicon microwires becomes the limiting factor.

Prof. Jurriaan Huskens, one of the researchers involved, states that 10.8 percent is the highest ever efficiency for a silicon-based design. However, a further increase in efficiency -- to fifteen percent -- is needed to make the technology economically viable.

Story Source:

Materials provided by University of Twente. Note: Content may be edited for style and length.


Journal Reference:

  1. Wouter Vijselaar, Pieter Westerik, Janneke Veerbeek, Roald M. Tiggelaar, Erwin Berenschot, Niels R. Tas, Han Gardeniers, Jurriaan Huskens. Spatial decoupling of light absorption and catalytic activity of Ni–Mo-loaded high-aspect-ratio silicon microwire photocathodes. Nature Energy, 2018; DOI: 10.1038/s41560-017-0068-x

Cite This Page:

University of Twente. "Solar fuels: better efficiency using microwires." ScienceDaily. ScienceDaily, 15 January 2018. <www.sciencedaily.com/releases/2018/01/180115121641.htm>.
University of Twente. (2018, January 15). Solar fuels: better efficiency using microwires. ScienceDaily. Retrieved June 11, 2019 from www.sciencedaily.com/releases/2018/01/180115121641.htm
University of Twente. "Solar fuels: better efficiency using microwires." ScienceDaily. www.sciencedaily.com/releases/2018/01/180115121641.htm (accessed June 11, 2019).

RELATED STORIES

FROM AROUND THE WEB

Below are relevant articles that may interest you. ScienceDaily shares links with scholarly publications in the TrendMD network and earns revenue from third-party advertisers, where indicated.
http://www.vxiaotou.com