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Solar-related projects in the Center:

  • Dye-sensitized solar cells
  • Quantum dot solar cells
  • Perovskite solar cells
  • Organic photovoltaics
  • Strain-tuning of semiconductors
  • Membranes and electrolyzers
  • Plasmonic nanostructures
  • Non-focusing concentrator optics
  • Mechanisms of electron, proton, and energy transfer
  • Artificial photosynthesis
  • Nanoparticle electrocatalysts
  • Photoelectrochemical water splitting
  • Photoelectrochemical conversion of CO2 to CO and other carbon-containing fuels

Selected research publications:

High pressure infiltration of porous fibers followed by laser annealing results in crystalline silicon wires with high anisotropic strain.  The bandgap of silicon can be strain-tuned between 0.59 and 1.10 eV by this technique.

Healy N., Mailis, S., Bulgakova, N.M., Sazio, P.J., Day, T.D., Sparks, J.R, Cheng, H.Y., Badding, J.V., and Peacock, A.C., “Extreme electronic bandgap modification in laser-crystallized silicon optical fibres.” Nature Mater. 13, 1122-7 (2014).

The rapid separation of electrons and holes is a key factor in determining efficiency in excitonic solar cells.  A study of fullerene-based organic solar cells shows that there is a critical size of fullerene crystallites, above which charge-transfer excited states become delocalized and photoinduced charge separation becomes efficient.

B. Bernardo, D. Cheyns, B. Verreet, R.D. Schaller, B.P. Rand, and N.C. Giebink, “Delocalization and dielectric screening of charge transfer states in organic photovoltaic cells”, Nature Commun. 5, 3245 (2014).

A kinetic analysis of water-splitting dye-sensitized solar cells identifies charge recombination pathways and explains the rapid photocurrent polarization that is frequently observed.

J. R. Swierk, N. S. McCool, T. P. Saunders, and T. E. Mallouk, "Effects of electron trapping and protonation on the efficiency of water-splitting dye-sensitized solar cells," J. Am. Chem. Soc., 136, 10974-10982 (2014).

Nanostructured transition-metal phosphides have recently emerged as Earth-abundant alternatives to platinum for catalyzing the hydrogen-evolution reaction (HER), which is central to several clean energy technologies because it produces molecular hydrogen through the electrochemical reduction of water.

Callejas, J.F., McEnaney, J.M., Read, C.G., Crompton, J.C., Biacchi, A.J., Popczun, E.J., Gordon, T.R., Lewis, N.S., and Schaak, R.E., “Electrocatalytic and Photocatalytic Hydrogen Production from Acidic and Neutral-pH Aqueous Solutions Using Iron Phosphide Nanoparticles,” ACS Nano. 8, 11101-7 (2014).

Flexible Si p-i-n junction fibers made by high pressure chemical vapor deposition offer new opportunities in textile photovoltaics and optoelectronics, as exemplified by their photovoltaic properties, gigahertz bandwidth for photodetection, and ability to waveguide light.

He, R., Day, T.D., Krishnamurthi, M., Sparks, J.R., Sazio, P.J., Gopalan, V., and Badding, J.V.,  “Silicon p-i-n junction fibers,” Adv Mater. 25, 1461-7 (2013).

Molecules at the electron donor/acceptor interfaces in organic photovoltaic materials have unique vibrational features. Using ultrafast vibrational spectroscopy, researchers can directly examine the dynamics of charge transfer state formation and dissociation.

Jeong, K.S., Pensack, R.D., and Asbury, J.B., “Vibrational spectroscopy of electronic processes in emerging photovoltaic materials,” Acc. Chem. Res., 46, 1538-47 (2013).



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