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nanotimes News in Brief

Solar Cells // Record-breaking Solar Cell

© Text: Penn State University

University, Ted Sargent at the University of Toronto in Canada and researcher at the King Abdullah University of Science & Technology (KAUST) in Saudi Arabia, created the most efficient colloidal- quantum-dot solar cell.

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“We figured out how to shrink the wrappers that encapsulate quantum dots down to the smallest imaginable size – a mere layer of atoms,” said Profes- sor Ted Sargent at University of Toronto, the corre- sponding author on the work and the holder of the Canada Research Chair in Nanotechnology. Quan- tum dots are nanoscale semiconductors that capture light and convert it into electrical energy. Because of their small size, the dots can be sprayed onto flexible surfaces, including plastics, enabling the production of solar cells that are less expensive than the existing silicon-based version.

Jiang Tang, Kyle W. Kemp, Sjoerd Hoogland, Kwang S. Jeong, Huan Liu, Larissa Levina, Melissa Furukawa, Xihua Wang, Ratan Debnath, Dongkyu Cha, Kang Wei Chou, Ar- minFischer,AramAmassian, John B. Asbury&E.H.Sargent: Colloidal-quantum-dot photovoltaics using atomic-ligand passivation, In: Nature, Volume 10(2011), No. 10, Octo- ber 2011, Pages 765-771, DOI:10.1038/nmat3118: http://dx.doi.org/10.1038/nmat3118

team of scientists that includes John Asbury, assistant professor of chemistry at Penn State

11-11/12 :: November/December 2011

Image, Left: Quantum dots capped with organic ligands. Bulky organic molecules (yellow and blue) has led to lower performance. Right: Quantum dots capped with the novel inorganic ligands reported in the work. Reduce bulk helped get elec- trons out, leading to record performance. © Sargent Lab, University of Toronto

R. Debnath, O. Bakr, E. H. Sargent: Solution-processed colloidal quantum dot photovoltaics: A perspective, In: Energy & Environmental Science, Vol. 4(2011), Issue 12, Pages 4870-4881, DOI:10.1039/c1ee02279b: http://dx.doi.org/10.1039/c1ee02279b