Solar-powered device captures carbon dioxide from air to make sustainable fuel

sc604 — Thu, 13 Feb 2025 10:00:00 +0000

̽��ֱ��researchers, from the ̽��ֱ�� of Cambridge, say their solar-powered reactor could be used to make fuel to power cars and planes, or the many chemicals and pharmaceuticals products we rely on. It could also be used to generate fuel in remote or off-grid locations.

Unlike most carbon capture technologies, the reactor developed by the Cambridge researchers does not require fossil-fuel-based power, or the transport and storage of carbon dioxide, but instead converts atmospheric CO2 into something useful using sunlight. ̽��ֱ��results are reported in the journal Nature Energy.

Carbon Capture and Storage (CCS) has been touted as a possible solution to the climate crisis, and has recently received £22bn in funding from the UK government. However, CCS is energy-intensive and there are concerns about the long-term safety of storing pressurised CO2 deep underground, although safety studies are currently being carried out.

“Aside from the expense and the energy intensity, CCS provides an excuse to carry on burning fossil fuels, which is what caused the climate crisis in the first place,” said Professor Erwin Reisner, who led the research. “CCS is also a non-circular process, since the pressurised CO2 is, at best, stored underground indefinitely, where it’s of no use to anyone.”

“What if instead of pumping the carbon dioxide underground, we made something useful from it?” said first author Dr Sayan Kar from Cambridge’s Yusuf Hamied Department of Chemistry. “CO2 is a harmful greenhouse gas, but it can also be turned into useful chemicals without contributing to global warming.”

̽��ֱ��focus of Reisner’s research group is the development of devices that convert waste, water and air into practical fuels and chemicals. These devices take their inspiration from photosynthesis: the process by which plants convert sunlight into food. ̽��ֱ��devices don’t use any outside power: no cables, no batteries – all they need is the power of the sun.

̽��ֱ��team’s newest system takes CO2 directly from the air and converts it into syngas: a key intermediate in the production of many chemicals and pharmaceuticals. ̽��ֱ��researchers say their approach, which does not require any transportation or storage, is much easier to scale up than earlier solar-powered devices.

̽��ֱ��device, a solar-powered flow reactor, uses specialised filters to grab CO2 from the air at night, like how a sponge soaks up water. When the sun comes out, the sunlight heats up the captured CO2, absorbing infrared radiation and a semiconductor powder absorbs the ultraviolet radiation to start a chemical reaction that converts the captured CO2 into solar syngas. A mirror on the reactor concentrates the sunlight, making the process more efficient.

̽��ֱ��researchers are currently working on converting the solar syngas into liquid fuels, which could be used to power cars, planes and more – without adding more CO2 to the atmosphere.

“If we made these devices at scale, they could solve two problems at once: removing CO2 from the atmosphere and creating a clean alternative to fossil fuels,” said Kar. “CO2 is seen as a harmful waste product, but it is also an opportunity.”

̽��ֱ��researchers say that a particularly promising opportunity is in the chemical and pharmaceutical sector, where syngas can be converted into many of the products we rely on every day, without contributing to climate change. They are building a larger scale version of the reactor and hope to begin tests in the spring.

If scaled up, the researchers say their reactor could be used in a decentralised way, so that individuals could theoretically generate their own fuel, which would be useful in remote or off-grid locations.

“Instead of continuing to dig up and burn fossil fuels to produce the products we have come to rely on, we can get all the CO2 we need directly from the air and reuse it,” said Reisner. “We can build a circular, sustainable economy – if we have the political will to do it.”

̽��ֱ��technology is being commercialised with the support of Cambridge Enterprise, the ̽��ֱ��’s commercialisation arm. ̽��ֱ��research was supported in part by UK Research and Innovation (UKRI), the European Research Council, the Royal Academy of Engineering, and the Cambridge Trust. Erwin Reisner is a Fellow of St John’s College, Cambridge.

Reference:
Sayan Kar et al. ‘Direct air capture of CO2 for solar fuels production in flow.’ Nature Energy (2025). DOI: 10.1038/s41560-025-01714-y

For more information on energy-related research in Cambridge, please visit the Energy IRC, which brings together Cambridge’s research knowledge and expertise, in collaboration with global partners, to create solutions for a sustainable and resilient energy landscape for generations to come.

Researchers have developed a reactor that pulls carbon dioxide directly from the air and converts it into sustainable fuel, using sunlight as the power source.

We can build a circular, sustainable economy – if we have the political will to do it

Erwin Reisner

Sayan Kar

Solar-powered flow reactor

̽��ֱ��text in this work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License. Images, including our videos, are Copyright © ̽��ֱ�� of Cambridge and licensors/contributors as identified. All rights reserved. We make our image and video content available in a number of ways – on our main website under its Terms and conditions, and on a range of channels including social media that permit your use and sharing of our content under their respective Terms.

Yes

Plastic: the new fantastic?

lw355 — Fri, 05 Jun 2020 09:30:20 +0000

Plastic has become a malevolent symbol of our wasteful society. It’s also cheap, durable, flexible, waterproof, versatile, lightweight, protective and hygienic.

During the coronavirus pandemic, plastic visors, goggles, gloves and aprons have been fundamental for protecting healthcare workers from the virus. But what about the effects on the environment of throwing away huge numbers of single-use medical protection equipment? How are we to balance our need for plastic with protecting the environment?

Released on 5 June 2020, World Environment Day, this new film considers how society might ‘reset the clock’ when it comes to living better with a vital material. We hear how Cambridge ̽��ֱ��'s Cambridge Creative Circular Plastics Centre (CirPlas) aims to eliminate plastic waste by combining blue-sky thinking with practical measures – from turning waste plastic into hydrogen fuel, to manufacturing more sustainable materials, to driving innovations in plastic recycling in a circular economy.

“Plastic is an example of how we must find ways to use resources without irreversibly changing the planet for future generations,” adds Professor Erwin Reisner, who leads CirPlas, which is funded by UK Research and Innovation.

Explore more:

Find further information on CirPlas

Plastic: the new fantastic?

Taylor Uekert studies the transformation of plastic waste into hydrogen fuel

̽��ֱ��text in this work is licensed under a Creative Commons Attribution 4.0 International License. Images, including our videos, are Copyright © ̽��ֱ�� of Cambridge and licensors/contributors as identified. All rights reserved. We make our image and video content available in a number of ways – as here, on our main website under its Terms and conditions, and on a range of channels including social media that permit your use and sharing of our content under their respective Terms.

Yes

̽��ֱ��'P' word

lw355 — Thu, 16 Jan 2020 08:00:00 +0000

How do we shift our 'take, make, throw-away' plastic world towards 'recycle, recover, re-use'? It's time for blue-sky thinking plus practical measures in the battle to reduce plastic waste.

̽��ֱ�� of Cambridge - circular economy

Solar-powered device captures carbon dioxide from air to make sustainable fuel

Plastic: the new fantastic?

Plastic: the new fantastic?

̽��ֱ��'P' word