U-M researchers working toward efficient harvesting of solar energy

May 04, 2011

At the University of Michigan College of Engineering, recent breakthroughs may lead to more effective means for harnessing the power of the sun.

Conventional means of collecting solar energy, for example, have been notoriously inefficient.

Now a team of chemical engineers at U-M is exploring new means of exploiting the abundant energy produced by Earth's nearest star. They have discovered a method for utilizing metal nano-particles, which act much like nanometer-sized light antennae, to help accelerate the production of renewable solar fuels and other chemicals.

The team, led by chemical engineering professor Suljo Linic, includes doctoral students David Ingram, Phillip Christopher and Hongliang Xin.

"The diffuse nature of solar light makes it very difficult to design processes that can convert the energy of sunlight into energy of at high rates," Linic said. "Our recent work shows that by using nano-particles with tailored optical properties, we can efficiently concentrate light and convert its energy into at higher rates."

Two important findings from the team's research have recently been published in leading chemistry journals. The first article, published in The , is titled " on Composite Plasmonic-Metal/Semiconductor Photoelectrodes: Evidence for Selective Plasmon-Induced Formation of Charge Carriers near the Semiconductor Surface." In it the team explores the use of silver nano-antennas to enhance the ability of a semiconductor catalyst to generate hydrogen fuel from water using solar energy.

The second paper, "Visible light enhanced catalytic oxidation reactions on plasmonic silver nanostructures," and published in Nature Chemistry, points out that currently all important industrial chemical reactions are driven by thermal energy, requiring massive fossil fuel inputs. Linic and his team have developed technology where a significant fraction of energy input to drive chemical reactions can be provided in the form of . This discovery paves the way toward a more environmentally friendly chemical industry using the power of the sun.

The research is funded by The National Science Foundation (NSF) and the Camille Dreyfus Teacher-Scholar Award from the Camille and Henry Dreyfus Foundation.

The university is pursuing patent protection for the intellectual property, and is seeking commercialization partners to help bring the technology to market.

Explore further: Thinnest feasible nano-membrane produced

More information: Water Splitting on Composite Plasmonic-Metal/Semiconductor Photoelectrodes: Evidence for Selective Plasmon-Induced Formation of Charge Carriers near the Semiconductor Surface, J. Am. Chem. Soc., 2011, 133 (14), pp 5202–5205 DOI: 10.1021/ja200086g

A critical factor limiting the rates of photocatalytic reactions, including water splitting, on oxide semiconductors is the high rate of charge-carrier recombination. In this contribution, we demonstrate that this issue can be alleviated significantly by combining a semiconductor photocatalyst with tailored plasmonic-metal nanostructures. Plasmonic nanostructures support the formation of resonant surface plasmons in response to a photon flux, localizing electromagnetic energy close to their surfaces. We present evidence that the interaction of localized electric fields with the neighboring semiconductor allows for the selective formation of electron/hole (e−/h+) pairs in the near-surface region of the semiconductor. The advantage of the formation of e−/h+ pairs near the semiconductor surface is that these charge carriers are readily separated from each other and easily migrate to the surface, where they can perform photocatalytic transformations.

add to favorites email to friend print save as pdf

Related Stories

Chemists shed light on solar energy storage

Dec 08, 2006

Chemistry's role in bridging the gap between solar energy's limited present use and enormous future potential was the topic of a recent article by MIT Professor Daniel G. Nocera and a colleague.

In the hands of scientists - the power of 10,000 Suns

Nov 04, 2005

Solar research at Paul Scherrer Institut (Switzerland) takes a leap into the future today with the opening of the High-flux Solar Simulator. With this new instrument scientists will be able to carry out experiments under ...

Photosynthesis: a new source of electrical energy

Feb 18, 2010

French scientists have transformed the chemical energy generated by photosynthesis into electrical energy. They thus propose a new strategy to convert solar energy into electrical energy in an environmentally-friendly ...

Renewable hydrogen energy - an answer to the energy crisis

Apr 19, 2007

Harvesting solar energy to produce renewable, carbon free and cost effective hydrogen as an alternative energy source is the focus of a new £4.2 million research programme at Imperial College London, it is announced.

Solar cells of the future

Dec 18, 2007

A new material, nano flakes, may revolutionise the transformation of solar energy to electricity. If so, even ordinary households can benefit from solar electricity and save money in the future.

Recommended for you

Thinnest feasible nano-membrane produced

Apr 17, 2014

A new nano-membrane made out of the 'super material' graphene is extremely light and breathable. Not only can this open the door to a new generation of functional waterproof clothing, but also to ultra-rapid filtration. The ...

Wiring up carbon-based electronics

Apr 17, 2014

Carbon-based nanostructures such as nanotubes, graphene sheets, and nanoribbons are unique building blocks showing versatile nanomechanical and nanoelectronic properties. These materials which are ordered ...

Making 'bucky-balls' in spin-out's sights

Apr 16, 2014

(Phys.org) —A new Oxford spin-out firm is targeting the difficult challenge of manufacturing fullerenes, known as 'bucky-balls' because of their spherical shape, a type of carbon nanomaterial which, like ...

User comments : 0

More news stories

'Exotic' material is like a switch when super thin

(Phys.org) —Ever-shrinking electronic devices could get down to atomic dimensions with the help of transition metal oxides, a class of materials that seems to have it all: superconductivity, magnetoresistance ...

Innovative strategy to facilitate organ repair

A significant breakthrough could revolutionize surgical practice and regenerative medicine. A team led by Ludwik Leibler from the Laboratoire Matière Molle et Chimie (CNRS/ESPCI Paris Tech) and Didier Letourneur ...