IBM Research (Yorktown Heights, NY) is developing a copper tin zinc sulfur selenium (CTZSS)-based solar cell using materials that it says are somewhat cheap and abundant, in contrast to copper indium gallium selenide (CIGS) and cadmium telluride (CdTe)—conventional technologies that have in the past suffered from indium and tellurium supply and price issues, as well as toxicity issues for the heavy metal Cd.
The CTZSS cell is manufactured using a solution-based approach, making it amenable to thin-film roll-to-roll or dip/spray processing. Early test cells had efficiency values of 9.6%—less than half that of crystalline silicon cells but still more than 40% better than previously achieved with this materials set. The combination of improved efficiency, indium-free absorber, and solution-based processing opens opportunities for development of a low-cost pervasive technology. Over the past several years, IBM researchers have pioneered several breakthroughs related to creating inexpensive, efficient solar cells. IBM does not plan to manufacture solar technologies but is open to partnering with solar-cell manufacturers to demonstrate the technology. Contact David Mitzi at [email protected].