A carbon nanofiber-based direct air capture filter built by UChicago.Elaina Eichorn/University of Chicago
A new nanofiber filter hints at a world where carbon capture hides inside every ceiling vent, quietly scrubbing indoor air while trimming electricity bills.
Researchers say this small, silent layer could scale into a global carbon sponge stitched into everyday infrastructure.
The technology comes from the University of Chicago’s Pritzker School of Molecular Engineering.
The team developed a distributed carbon nanofiber direct air capture (DAC) filter designed to slip into standard ventilation systems.
A life-cycle analysis shows the filter is 92.1 percent efficient even after accounting for emissions from manufacturing and disposal.
The study’s first author Ronghui Wu said, “Every building already has ventilation systems that move large volumes of air every day… It’s a practical and scalable way to make carbon capture part of everyday infrastructure.”
Every day vents, upgraded
Researchers say the potential is enormous. Swapping existing filters for DAC filters across the global building stock could remove up to 596 megatonnes of CO2 annually, roughly equivalent to taking 130 million cars off the road.
The individual benefits are more intimate: smaller electricity bills. A 2024 study suggests savings could reach 21.66 percent for households and offices adopting the system.
Wu explained the mechanism succinctly: “Our filter removes carbon dioxide inside the building, so the system doesn’t have to bring in as much outside air. That means less air needs to be heated or cooled.”
The core material is a carbon nanofiber–based polyethylenimine (PEI) compound engineered to drop straight into existing HVAC frames, much like HEPA filters.
But unlike HEPA units that end up in landfills every six to twelve months, these DAC filters can be regenerated and returned to duty.
That regeneration is where the system becomes even more compelling. The filters were designed with strong solar absorptivity, enabling CO2 removal through solar-thermal heating.
In Hsu’s words: “It has to be able to regenerate using renewable energy.”
Sunlight powers recovery
Current DAC giants require dedicated plants, land, and continuous power. By contrast, this design leans into decentralization. Hsu compared it to the evolution of solar power: once locked behind utility fences, now spread across rooftops.
“CO2 from air is similar,” he said. “We propose, using experiment and computation to demonstrate, that indeed we could retrofit our buildings to be part of the decarbonization effort.”
The team envisions a municipal loop in which saturated filters are collected alongside garbage and recycling, transported to central hubs, stripped of CO2, and reissued.
Hsu described the concept: “They would have these saturated filters from household ventilation systems and commercial buildings… They’d ship the saturated one to a centralized facility to dissolve the CO2 or make it into highly concentrated CO2 to capture or, even better, convert to high-value chemicals or fuel.”
Beyond climate gains and energy savings, the technology carries day-to-day health advantages. Wu noted, “This kind of air filter can also improve indoor air quality, especially in places like classrooms and offices where many people share the same space.”
The research appears in Science Advances.