A breakthrough technology developed by engineers at Oregon State University makes use of sunlight itself to expedite the manufacture of ultra-thin solar materials.

The new production technology, developed by chemical engineers from Oregon State University, has the potential to make sunlight the key driver behind the full gamut of the solar energy process by applying it to the manufacture of the very materials used in photovoltaic devices.

The method involves the use of a "continuous flow" solar microreactor which is capable of exploiting the sun's radiation to generate heat for the production of photovoltaic nanoparticle inks.

The nanoparticle inks are an essential ingredient in the manufacture of ultra-thin printed photovoltaic cells, which possess distinct advantages over conventional photovoltaic devices due to the extreme fineness of their solar absorbing layers.

solar diagram

While conventional silicon cells have solar absorbing layers which are between 50 and 100 microns in thickness, those of thin film cells measure only one to two microns, enabling them to achieve conversion efficiencies as high as 20 per cent in the laboratory.

The widespread usage of such nanoparticle inks for the production of commercial solar cells has thus far been hampered, however, by batch manufacturing processes which are comparatively expensive and time-consuming.

According to Chih-hung Chang, professor of chemical engineering at Oregon State University and the lead author of a study on the technology which has been published in RSC Advances, the new process makes the manufacture of nanoparticle inks quick and economical.

"Our system can synthesise solar energy materials in minutes compared to other processes that might take 30 minutes to 20 hours," Chang said. "This gain in operation speed can lower costs."

Chang further notes that in addition to being economical, the process is also environmentally friendly, given that it depends upon the sun's energy to power the microreactor.

"Several aspects of this system should continue to reduce the cost of solar energy, and when widely used, our carbon footprint," said Chang. "It could produce solar energy materials anywhere there's an adequate solar resource, and in this chemical manufacturing process, there would be zero energy impact."