2013年6月20日星期四

Dark discovery could double solar cell efficiency

Dark discovery could double solar cell efficiency


LONDON – The efficiency of solar cells could be doubled by the discovery of a quantum "shadow state" that allows two – rather than one – high-energy electrons to be produced by optoelectronic energy conversion. The latest research on the mechanisms of solar energy conversion was led by chemistry Professor Xiaoyang Zhu at The University of Texas at Austin and was published in Science magazine.

Zhu and his team have discovered that it's possible to double the number of electrons harvested from one photon of sunlight using pentacene, an organic plastic semiconductor material.

"Plastic semiconductor solar cell production has great advantages, one of which is low cost," said Zhu, in a statement. "Combined with the vast capabilities for molecular design and synthesis, our discovery opens the door to an exciting new approach for solar energy conversion, leading to much higher efficiencies."

The maximum theoretical efficiency of the silicon solar cell in use today is approximately 31 percent. This is because much of the photonic energy hitting the cell is not that at wavelengths that can be turned into usable electricity. That energy is instead lost as heat. Capturing the thermally excited hot electronic energy could potentially increase the efficiency of solar-to-electric power conversion to as high as 66 percent, according to the research team.

Zhu and his team previously demonstrated that those hot electrons could be captured using semiconductor nanocrystals. They published that research in Science in 2010, but Zhu says the actual implementation of a viable technology based on that research is very challenging. The primary one being that it requires focused sunlight rather than ambient light that typically hits a solar panel.

Zhu and his team have found an alternative. They discovered that in the semiconductor pentacene a photon produces a dark quantum "shadow state" from which two electrons can then be efficiently captured to generate more energy.

The absorption of a photon creates an excited electron-hole pair, called an exciton. The exciton is coupled quantum mechanically to a dark "shadow-state" called a multi-exciton. It so happens that the multi-exciton can be an efficient source of two electrons via transfer to an electron acceptor material such as fullerene, the ball-shaped 60-atom allotrope of carbon, which was used in the study. Exploiting this could raise pentacene solar cell efficiency to 44 percent without the need for a focused solar beam, according to the researchers.

The research team was led by Wai-lun Chan, a postdoctoral fellow in Zhu's group, with the help of postdoctoral fellows Manuel Ligges, Askat Jailaubekov, Loren Kaake and Luis Miaja-Avila.


Related links and articles:

Dark state announcement

News articles:

Heliatek achieves 9.8 percent organic solar cell efficiency

Solar firm claims efficiency record

Sharp claims world's highest solar cell conversion efficiency of 35.8 percent


Welcome to SUV System Ltd!

SUV System Ltd is ISO 90012008 Certified electronics distributor with 10 years of experiences.

We have built up long term business relationship with about many companies which are stockers and authorized agents. we have a steady and reliable supply to meet customer's demands to the greatest extent .Confidently, we are able to lower your cost and support your business with our years of professional service.

SUV System Ltd is Electronic Components Distributor Supplies,Find Quality Electronic Components Supplies Products IC(Integrated Circuits),Connectors,Capacitor,Resistors,Diodes,Transistors,LED at Suvsystem.com. Sourcing Other Energy, Environment, Excess Inventory Products from Manufacturers and Suppliers at Suvsystem.com

Electronic Components distributor:http://www.suvsystem.com

Connectors Distributor:http://www.suvsystem.com/l/Connectors-1.html

IC Distributor:http://www.suvsystem.com/l/IC(Integrated-Circuits)-1.html

LED Distributor:http://www.suvsystem.com/l/LED-1.html

Capacitor Distributor:http://www.suvsystem.com/l/Capacitor-1.html

Transistor Distributor:http://www.suvsystem.com/l/Transistors-1.html

Resistor Distributor:http://www.suvsystem.com/l/Resistors-1.html

Diode Distributor:http://www.suvsystem.com/l/Diodes-1.html

SUV System Ltd insists on the managing faith ofsincereness,speciality,foresight, win-win,so we build up stable-relationship customers located all over the world, including the States, Europe, Argentina, UAE, Malaysia, Australia,and India etc

we are focus on the following fields,and hope we can help you.


C0402C369C4GACTU C0402C369C4GAC C0402C369C3GACTU C0402C369B5GACTU C0402C361M5HAC C0402C361M3HAC C0402C361M1HAC C0402C361K5HACTU C0402C361K5HAC C0402C361K5GACTU C0402C361K5GAC C0402C361K3HACTU C0402C361K3HAC C0402C361K1HACTU C0402C361K1HAC C0402C361K1GACTU C0402C361J5HACTU C0402C361J5HAC C0402C361J3HACTU C0402C361J3HAC C0402C361J1HACTU C0402C361J1HAC C0402C361G5GAC C0402C391J4RAC C0402C391J4GAC7867 C0402C391J4GAC C0402C391J3RAC7867 C0402C391J3RAC C0402C391J3HACTU C0402C391J3HAC C0402C391J1HACTU C0402C391J1HAC C0402C391J1GACTU C0402C391G5GAC C0402C391G1GACTU C0402C391F8GAL C0402C391F5GAC C0402C391F1GACTU C0402C390M3GAC C0402C390K8GACTU
http://www.suvsystem.com/a/3034.aspx