Novel Reactive Ink Prints Into Everlasting Copper

The once-unavoidable verdigris that turned copper surfaces green—and inspired “green rot” war anecdotes—may no longer be inevitable. A new University of Maryland invention has demonstrated a way to stop the copper degradation cycle altogether.

Researchers have developed a liquid reactive ink that can print copper onto nearly any surface without oxidation or corrosion. Shenqiang Ren, a professor in the Department of Materials Science and Engineering, along with Professor Liangbing Hu from Yale University, and Senior Scientist Haimei Zheng from the Lawrence Berkeley National Laboratory, led a collaborative effort that spanned over a decade of discovery. The results of this work were published in the journal Science today, and was selected as the cover article.

Copper, a hidden backbone in modern life, carries electricity in many technologies, including AI systems, data centers, wireless networks, circuit boards, solar panels, and batteries. Given the broad impact across multiple industries, the reactive ink could enable lower-cost AI infrastructure, more efficient data centers, flexible and lightweight radio frequency electronics, simpler circuit boards manufacturing, and more affordable solar and battery systems.

“These printed copper traces act as the “wiring” inside next-generation electronics, produced faster, cheaper, and with less waste,” said Ren.

Using a versatile blue ink, the team created a fast, low-temperature method of 150 degrees Celcius to create copper that remains stable over time. This breakthrough addresses two long-standing challenges in the field: developing printable copper inks under ambient conditions and preventing it from corrosion and oxidation.

To demonstrate the technique’s versatility, the researchers printed copper conductor traces for solar cells, circuit boards, small scale replicas of the Testudo statue, and even models of the Eiffel Tower. Additional testing showed the material’s ability to remain intact after six months of seawater submersion.

This new approach could replace conventional copper processing methods such as plating and chemical etching, reducing time, cost, and environmental impact. Given copper’s widespread use—especially in electronics manufacturing, which accounts for about 60% of demand—the innovation could have broad industrial implications as demand rises with the expansion of AI and data centers.

“The newly developed ink has the potential to revolutionize the conductive ink industry by enabling the use of copper instead of more expensive metals, such as silver, across electronic, energy, and environmental applications,” said Hu, who collaborated on this study during his time as a UMD faculty.

Looking to introduce the technology into the market, a UMD startup, NewCopper, co-founded by Ren and Hu, aims to commercialize the ink.

Published May 14, 2026