Copper, zinc, and tin. These three relatively available metals react into copper zinc tin sulfide nanoparticles, recognized as a promising material that can be applied like ink to produce solar cells.
Researchers at Oregon State University have given hopes for this compound a boost, by demonstrating a cheap "one-pot" technique that uses microwaves instead of conventional heat sources to reduce manufacturing time and improve process control.
Greg Herman, of the School of Chemical, Biological and Environmental Engineering at OSU notes:
All of the elements used in this new compound are benign and inexpensive, and should have good solar cell performance. This approach should save money, work well and be easier to scale up at commercial levels, compared to traditional synthetic methods. Microwave technology offers more precise control over heat and energy to achieve the desired reactions.
Many solar cell technologies rely on rarer resources, such as indium, raising fears that the growth of solar technology could be limited by the availability of raw materials. The more readily available copper, tin, and zinc address this issue. These metals also present lower hazards to workers producing solar devices or handling end-of-life electronics, compared to many other materials that show promising photovoltaic properties.
Researchers say that compounds synthesized using the new microwave technique have already been used to produce nanoparticles inks that were themselves used to successfully fabricate a printed photovoltaic device.