5 March 2009

Solar sandwich: Hold the silicon, please

By layering plastics and other materials, Canadian researchers are extracting electricity from the sun without expensive silicon.

The Canada’s National Institute for Nanotechnology (NINT) and the University of Alberta have engineered an approach that is leading to improved performance of plastic solar cells (hybrid organic solar cells).

The development of inexpensive, mass-produced plastic solar panels is a goal of intense interest for many of the world’s scientists and engineers because of the high cost and shortage of the ultra-high purity silicon and other materials normally required.

Jillian Buriak, a professor of chemistry at the U of A, NINT principal investigator, and member of the research team, uses a simple analogy to describe the approach: “Consider a clubhouse sandwich, with many different layers. One layer absorbs the light, another helps to generate the electricity, and others help to draw the electricity out of the device. Normally, the layers don’t stick well, and so the electricity ends up stuck and never gets out, leading to inefficient devices. We are working on the mayonnaise, the mustard, the butter, and other ‘special sauces’ that bring the sandwich together and make each of the layers work together. That makes a better sandwich, and makes a better solar cell in our case.”

After two years of research, these U of A and NINT scientists have, by only working on one part of the sandwich, seen improvements of about 30% in the efficiency of the working model.

The end goal is to produce plastic solar cell material that ink-jet printers will make cheaply, quickly, and in massive quantities.

For related information, go to www.isa.org/environment.