Research Groups

Research Group 2: Solar Spectrum Control and Conversion

RG Leader: John Rogers
Affiliated PIs: Paul Alivisatos, Harry Atwater, Paul Braun, Mark Brongersma, Jennifer Dionne, Shanhui Fan, Ralph Nuzzo, Eli Yablonovitch, and Xiang Zhang


Downshifting luminescent concentrator with micro solar cells (J. Rogers & R. Nuzzo, UIUC)

The most substantial near-term opportunity for increase in solar energy conversion efficiency is via exploitation of the full solar spectrum. As first discussed by Shockley and Quiesser, photovoltaic conversion efficiency in solar cells has conventionally been limited by the excitation of electron-hole pairs across a semiconductor energy gap. There is now a well-defined set of physical processes that can in principle overcome this ‘Shockley-Quiesser limit’ of one photogenerated electron-hole pair per photon of above energy gap energy, and these ideas are now receiving increased attention and research. The work conducted by the RG2 team will investigate strategies for solar spectrum control and conversion that will enable >40% photovoltaic conversion efficiency, exploiting spectrum splitting in novel architectures, photon recycling, and photon upconversion and downshifting in concentrating schemes. 


RG2 research projects include:

  • Solar spectrum conversion and control exploiting the physics of photon recycling
  • Integrated 3D structures for dispersive spectral splitting
  • Advanced photonic materials for spectral conversion