Safe salt could yield cheaper, more efficient solar cells

Cadmium telluride solar cells could be made at a lower cost if magnesium chloride is used in the production process instead of cadmium chloride.

NREL

A cheap, safe salt could be the key ingredient for concocting efficient solar cells.

Right now, the most efficient solar cells are made with a layer of cadmium telluride, which absorbs more sunlight and converts more of it to energy than silicon solar cells. However, cadmium telluride solar cells are made with cadmium chloride, an expensive and highly toxic salt.

To cut costs and toxicity, scientists instead tried making cadmium telluride solar cells with magnesium chloride, a cheap, benign salt. Tests show that the solar cells made with the safer salt are as efficient as those made with cadmium chloride, researchers report June 26 in Nature.

Ashley Yeager is the associate news editor at Science News. She has worked at The Scientist, the Simons Foundation, Duke University and the W.M. Keck Observatory, and was the web producer for Science News from 2013 to 2015. She has a bachelor’s degree in journalism from the University of Tennessee, Knoxville, and a master’s degree in science writing from MIT.