Researchers develop artificial plants that purify indoor air, generate electricity

BINGHAMTON, N.Y. -- On average, Americans spend about 90% of their time indoors, and the air we breathe at work, school or home affects our overall health and well-being. Most air purification systems, however, are expensive, cumbersome and require frequent cleaning or filter replacement to function at optimum levels.

Binghamton University, State University of New York Professor Seokheun “Sean” Choi and PhD student Maryam Rezaie are repurposing their research about bacteria-powered biobatteries — ingestible and otherwise — into a new idea for artificial plants that can feed off carbon dioxide, give off oxygen and even generate a little power. The artificial plants use indoor light to drive photosynthesis, achieving a 90% reduction in carbon dioxide levels — far surpassing the 10% reduction seen with natural plants.

They outline their results, which is partially supported by the Office of Naval Research, in a paper recently published by the journal Advanced Sustainable Systems.

“Especially after going through COVID-19, we know the significance of indoor air quality,” said Choi, a faculty member in the Thomas J. Watson College of Engineering and Applied Science’s Department of Electrical and Computer Engineering. “Many sources can generate very toxic materials, like building materials and carpets. We breathe out and breathe in, and that builds up carbon dioxide levels. Also, there are risks from cooking and infiltration from the outdoors.”

Using five biological solar cells and their photosynthetic bacteria, Choi and Rezaie created an artificial leaf “for fun,” then realized the concept has wider implications. They built the first plant with five leaves, then tested its carbon dioxide capture rates and oxygen generation capability.

Although power generation around 140 microwatts is a secondary benefit, Choi hopes to improve the technology to achieve a minimum output of more than 1 milliwatt. He also wants to integrate an energy storage system, such as lithium-ion batteries or supercapacitors.

“I want to be able to use this electricity to charge a cell phone or other practical uses,” he said.

Other upgrades could include using multiple bacteria species to ensure long-term viability and developing ways to minimize maintenance, such as water and nutrient delivery systems.

“With some fine-tuning, these artificial plants could be a part of every household,” Choi said. “The benefits of this idea are easy to see.”