Minnesota iron ore could be key to sustainable and lower-cost semiconductor

MINNEAPOLIS / ST. PAUL (08/31/2026) — For the first time, researchers led by CEMS’ Chris Leighton, Distinguished McKnight University Professor, have demonstrated that the low-purity iron ore prevalent in Minnesota can be used to create semiconductor-quality iron sulfide, also known as “fool’s gold” or pyrite. This discovery could have cost-effective and sustainable applications in future electronic devices and more.

Pyrite iron sulfide is a unique semiconductor as it absorbs light extraordinarily well, is composed of very abundant elements, along with being non-toxic and cost-effective. Synthesizing high-quality semiconducting pyrite directly from an abundant iron resource like the Iron Range is therefore appealing, but semiconductors are extremely sensitive to impurities and defects, making this very challenging.

In this work the researchers took iron ore samples directly from the Minnesota Iron Range and demonstrated that they can be used to synthesize semiconductor-quality fool’s gold using simple processes. This discovery took the researchers by surprise. 

“We realized that pyrite's really not like a typical semiconductor - it is surprisingly immune to impurities,” said Professor Leighton. “So, we wondered, do we even need the high purity material that we (and everyone else) had been using to make semiconducting pyrite.”

"There are all sorts of reasons why you would think this would not be possible,” Leighton added. “But, during processing the dirty — or low-purity — iron ores, directly from the Minnesota Iron Range, were easily converted to semiconductor-quality pyrite with no extra purification steps. This happens for reasons that we now understand pretty well.”

This discovery could open up a new revenue stream for a global industry, with a broad spectrum of applications in clean energy technologies, based on a natural resource found abundantly in Minnesota.

This work was funded by the Minnesota Environment and Natural Resources Trust Fund (ENTRF) as recommended by the Legislative Citizen Commission on Minnesota Resources (LCCMR). The ENRTF is a permanent fund in Minnesota that provides funding for the protection and conservation of Minnesota's natural resources. This work was completed in collaboration with the University of Minnesota Characterization Facility and the Minnesota Nano Center.

Read the full story about this exciting new research at the CSE website.

Read the paper entitled, “Semiconductor-Quality Pyrite FeS2 from Iron Ore,” on the APS Journals website, first-authored by CEMS graduate student Yeon Lee 

Learn more about Professor Leighton’s work at the Leighton Research Group website.