Groundbreaking crystals promise cleaner, cheaper gas purification
A team of researchers from the University of Strathclyde and the University of Sheffield has unveiled a new class of crystal-based materials that could transform how gases are separated in industrial settings. Published in Nature Chemistry, the study describes non-porous silver coordination polymers that capture carbon dioxide (CO₂) through a dissolution-like mechanism rather than traditional sieving. The development could lead to more energy-efficient purification processes for natural gas, hydrogen production, and carbon capture, with the potential to significantly reduce emissions from gas use.
The core idea is simple in concept but novel in practice: instead of forcing gas molecules through tiny pores, these crystals respond to pressure by creating temporary openings that selectively trap CO₂ while releasing methane, the main component of natural gas. This selective behavior could yield a purer product with less energy input compared to conventional adsorption or filtration methods that rely on fixed pore networks.
How the dissolution-like mechanism works
In conventional gas separation, materials with fixed pores act as sieves, allowing certain molecules to pass while blocking others. The new crystals, however, are lined with fluorine-based chains that react to pressure by forming fleeting apertures. When a gas mixture is present, CO₂ interacts with the surface in a way that resembles dissolution in certain liquids, effectively “hiding” CO₂ temporarily inside the crystal while methane is driven out. When pressure conditions change, the CO₂ is released in a controlled manner, enabling a cleaner, purified gas product.
Researchers highlight that this mechanism can be tuned. By adjusting the length of the molecular chains inside the crystals, the team can tweak at which pressures CO₂ capture occurs and how readily the material releases it. That tunability is crucial for adapting the material to different industrial environments, whether in natural gas processing facilities or carbon capture systems paired with hydrogen production.
Why this matters for industry and the climate
Gas separation is a cornerstone of modern energy systems. CO₂ removal from mixed gases helps mitigate emissions during natural gas production and supports processes that produce low-carbon hydrogen. The reported materials promise several advantages: lower energy requirements, reduced operational costs, and flexibility to function across a range of temperatures and pressures. If proven scalable, the crystals could complement or even replace some existing purification technologies, hastening the transition away from fossil fuels without sacrificing efficiency.
Professor Ashleigh Fletcher of the University of Strathclyde emphasized the broader potential: “Our discovery that non-porous silver coordination polymers can selectively capture CO₂ through a dissolution-like mechanism opens up exciting possibilities for next-generation gas separation technologies.” The collaboration with Sheffield researchers demonstrates how cross-institution teamwork can accelerate practical breakthroughs that matter for industry and climate goals.
From lab discovery to real-world use
As with many scientific breakthroughs, the path to commercial deployment involves addressing scale, durability, and cost. The research team is optimistic about translating the technique into pilot systems that can handle industrial gas streams. Key questions include how the materials perform over extended cycling, how they resist impurities commonly found in industrial gases, and how fabrication costs compare to existing CO₂ capture and gas separation technologies.
Beyond natural gas purification, the materials may find roles in carbon capture, hydrogen generation, and other sectors where selective gas separation is critical. The ability to fine-tune the material by chain length offers a strategic lever for adapting to diverse operating conditions, potentially expanding the technology’s applicability across the energy transition.
Looking ahead
Researchers plan to explore the long-term stability of these non-porous coordination polymers, optimize synthesis routes for scale-up, and assess performance across real-world gas mixtures. As the world seeks cleaner energy solutions, innovations like these could provide practical, cost-effective tools to reduce CO₂ emissions while maintaining reliable, affordable gas supplies.
Conclusion
By reimagining how gases interact with solid materials, the Strathclyde-Sheffield team has opened a promising avenue in gas purification. If the dissolution-like mechanism proves robust at scale, these crystals could help industry cut energy use and emissions, supporting cleaner natural gas operations and advancing carbon management efforts.
