There are two key factors that affect solar cell performance: high optical transparency for good light transmission, and high optical haze for increased scattering, and therefore absorption. Researchers recently developed an inexpensive paper solar panel component made from wood fibers that is more environmentally-friendly than the plastic substrates currently used, and it has 96 percent transparency and an unrivalled optical haze of 60 percent. Could this be the most efficient solar cell yet?

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What makes this new paper so exciting is that current materials with high transparency values are often plagued by low optical haze values. The isn’t the case for this particular paper because of its nanoporous, rather than microporous structure. Researchers achieved this structure with a treatment called TEMPO, which weakens the hydrogen bonds between the microfibers in the wood, causing them to swell up and collapse into a dense, tightly-packed structure containing nanopores.

Although there are other papers made of nanofibers, this paper demonstrates a much higher optical transmittance, while using much less energy and time for processing. Because it’s also easy to apply the material as a laminate, the highly transparent, high-haze paper could offer an cost-effective way to enhance the efficiency of solar panels, solar roofs, and solar windows already in place.

The team responsible for this potentially revolutionary technology is composed of researchers from the University of Maryland, the South China University of Technology, and the University of Nebraska-Lincoln, who also published a  on the new material in a recent issue of Nano Letters.

“We would like to work with solar cell and display companies to evaluate the applications,” coauthor Liangbing Hu, Assistant Professor in the Department of Materials Science and Engineering at the University of Maryland, told


Images by Rich AndersonZEISS Microscopy