
Scientists at the University of California, Riverside, have found a way to manage efficient solar energy conversion using the infrared region of the lightwave spectrum.
The team has combined inorganic semiconductor nanocrystals with organic molecules to ‘up-convert’ photons in the solar spectrum’s infrared region.
The process is said to improve solar photovoltaic efficiencies by 30% or more, the team said.
University of California, Riverside, chemistry professor Christopher Bardeen said: "The infrared region of the solar spectrum passes right through the photovoltaic materials that make up today’s solar cells."
Scientists have used cadmium selenide and lead selenide semiconductor nanocrystals, and organic compounds, including diphenylanthracene and rubrene.
"The hybrid material we have come up with first captures two infrared photons that would normally pass right through a solar cell without being converted to electricity, then adds their energies together to make one higher energy photon," Bardeen added.
"This upconverted photon is readily absorbed by photovoltaic cells, generating electricity from light that normally would be wasted."
The team focused 980nm infrared light at the hybrid material, and observed that it generated upconverted orange / yellow fluorescent 550nm light.
Upconverting two low-energy photons into one high-energy photon could benefit biological imaging, data storage and organic light-emitting diodes.
Supported by grants from the National Science Foundation and the US Army, research was conducted by co-authors Zhiyuan Huang, Xin Li, Melika Mahboub, Kerry Hanson, Valerie Nichols and Hoang Le.
The provisional patent on the technology has been filed by UCR Office of Technology Commercialization.
Image: Solar panels for efficient, renewable energy conversion. Photo: courtesy of David Monniaux.