Tag Archives: carbon nanofiber

With new nanofiber filter, air conditioners, heaters and other ventilation systems could remove airborne carbon dioxide

A November 13, 2025 news item on Nanowerk announces work that could cut energy costs while removing airborne carbon dioxide, Note: Links have been removed,

A nanofiber air filter developed by the University of Chicago Pritzker School of Molecular Engineering (UChicago PME) could turn existing building ventilation into carbon-capture devices while cutting homeowners’ energy costs.

In a paper published in Science Advances (“Distributed direct air capture by carbon nanofiber air filters”), researchers from the lab of UChicago PME Asst. Prof. Po-Chun Hsu developed a distributed carbon nanofiber direct air capture (DAC) filter that could potentially turn every home, office, school or other building into a small carbon-capture system working toward the global problem of airborne CO2.

A life-cycle analysis shows that – even after factoring extra CO2 released by everything from manufacture and transportation to maintenance and disposal – the new filter is 92.1% efficient in removing carbon dioxide from the air.

A November 11, 2025 University of Chicago news release (also on EurekAlert) by Paul Dailing, which originated the news item, delves further into the research, Note: Links have been removed,

“Every building already has ventilation systems that move large volumes of air every day. By integrating our carbon-capture filters into these systems, we can remove carbon directly from the air without building new plants or using extra land,” said first author Ronghui Wu, an assistant professor at Nanyang Technological University who was a postdoctoral researcher in Hsu’s lab at the time of the research. “It’s a practical and scalable way to make carbon capture part of everyday infrastructure.”

On the largest possible level, replacing every building air filter with this new model could remove up to 596 megatonnes of carbon dioxide from the air – the equivalent of taking 130 million cars off the road for a year.

But on the individual level, every home, office or school that switch to DAC filters should expect lower energy bills. One study from 2024 indicated those savings could be up to 21.66%.

“Normally, air-conditioning systems need to pull in a lot of outside air to keep indoor carbon dioxide levels low,” Wu said. “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, which reduces the energy consumptions in HVAC.”

Regenerated by sunlight

Current direct air capture technologies are massive, corporate-owned affairs requiring major investments in land, power and other resources. Hsu likens it to solar power – a technology once confined to utility-owned solar farms, but now a network of large farms and small rooftop panels working toward the same energy goal.

“These rooftop panels are possible because sunlight is more or less uniform. The CO2 from air is similar,” Hsu said. “We propose, using experiment and computation to demonstrate, that indeed we could retrofit our buildings to be part of the decarbonization effort.”

Creating a practical, real-world filter is a balancing act. The UChicago PME team had to ensure that the filter removes more CO2 from the air than the amount added by manufacturing, transporting, installing, maintaining and eventually disposing of the filters.

The team’s carbon nanofiber–based polyethylenimine (PEI) material would create a reusable filter that could slot into existing HVAC systems, similar to the air-purifying high efficiency particulate arresting (HEPA) filters. Unlike HEPA filters, which head to landfills as garbage every six months to a year, the carbon-capture filters would have the CO2 removed regularly and be returned to service.

Hsu and Wu envision an ecosystem where municipal waste management systems haul off the filters weekly with the garbage and recycling.

“They would have these saturated filters from household ventilation systems and commercial buildings, then replace them with new ones,” Hsu said. “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.”

The new material was specifically designed to show excellent solar absorptivity. This means the CO2 can be removed from a saturated filter through solar thermal methods – including literally leaving the filter out under the sun.

“It has to be able to regenerate using renewable energy,” Hsu said. “The most common way to regenerate CO2 with solvent, is by heating it up. If you burn fossil fuels to heat up the solvent, then you will probably end up emitting more carbon dioxide than you capture.”

While the global benefits would rise as more places adopt the filter, lower energy bills aren’t the only benefits an individual would see from installing a direct air capture filter.

“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,” Wu said. “By keeping indoor carbon dioxide levels low, it helps people stay more alert, focused, and healthy.”

Here’s a link to and a citation for the paper,

Distributed direct air capture by carbon nanofiber air filters by Ronghui Wu, Hernan E. Delgado, Yi Xie, Yuanke Chen, Gangbin Yan, Edward Luo, Qizhang Li, Qingsong Fan, Yu Han, Genesis M. Higueros, Amar Ruthen, Chenxi Sui, Adarsh Suresh, David B. Mitzi, Chong Liu, Amgad Elgowainy, and Po-Chun Hsu. Science Advances 17 Oct 2025 Vol 11, Issue 42 DOI: 10.1126/sciadv.adv6846

This paper is open access.

Teijin and its fibres at Nano Tech 2016

Teijin is a Japanese chemical and pharmaceutical company known to me due to its production of nanotechnology-enabled fibres. As a consequence, a Jan. 21, 2016 news item on Nanotechnology Now piqued by interest,

Teijin Limited announced today that it will exhibit a wide range of nanotech materials and products incorporating advanced Teijin technologies during the International Nanotechnology Exhibition and Conference (nano tech 2016), the world’s largest nanotechnology show, at Tokyo Big Sight in Tokyo, Japan from January 27 to 29 [2016].

A Jan. 21, 2016 Teijin news release, which originated the news item, offers further detail,

Teijin’s booth (Stand 4E-09) will present nanotech materials and products for sustainable transportation, information and electronics, safety and protection, environment and energy, and healthcare, including the following:

– Nanofront, an ultra-fine polyester fiber with an unprecedented diameter of just 700 nanometers, features slip-resistance, heat shielding, wiping and filtering properties. It is used for diverse applications, including sportswear, cosmetics and industrial applications such as filters and heat-shielding sheets.

– Carbon nanotube yarn (CNTy) is 100%-CNT continuous yarn offering high electrical and thermal conductivity, easy handling and flexibility. Uses including space, aerospace, medical and wearable devices are envisioned. A motor using CNTy as its coil, developed by Finnish Lappeenranta University of Technology Opening a new window, will be exhibited first time in Japan.

– NanoGram Si paste is a printed electronics material containing 20nm-diameter silicon nanoparticles for photovoltaic cells capable of high conversion efficiency.

– Teijin Tetoron multilayer film is a structurally colored multilayer polyester film that utilizes the interference of each multilayer’s optical path difference rather than dyes or pigments. Decorative films for automotive and other applications will be exhibited.

– High-performance membranes, including a high-precision porous thin polyethylene membrane and multilayer membrane composites for micro filters, are moisture-permeable waterproof sheets.

– Carbon Alloy Catalyst (CAC) (under development) is platinum free catalyst made from polyacrylonitrile (precursor of carbon fiber) in combination with iron species, which is less expensive and more readily available than platinum, enabling production for reduced cost and in higher volumes. Fuel cells in which the cathode consists of the CAC without the platinum catalyst can generate exceptionally high electric power.

– Carbon nanofiber (under development) is a highly conductive carbon nanofiber with an elliptical cross section consisting of well-developed graphite layers ordered in a single direction. Envisioned applications include additives for  lithiumion secondary batteries (LIBs) , thermal conducting materials and plastic-reinforcing materials, among others.

Teijin first came to my attention in 2010 with their Morphotex product, a fabric based on the nanostructures found on the Blue Morpho butterfly’s wing. I updated the story in an April 12, 2012 posting sadly noting that Morphotex was no longer available.

For anyone interested in the exhibition, here’s the nano tech 2016 website.