Scientists Unlock High-Energy Polymer from Carbon Dioxide Mixture, Paving Way for New Materials
A groundbreaking study has revealed a novel method for creating a recoverable, high-energy polymer from a carbon monoxide and oxygen mixture, potentially revolutionizing the development of propellants, explosives, and other advanced materials.
Researchers at Lawrence Livermore National Laboratory (LLNL) have identified a first-of-its-kind carbon dioxide-equivalent polymer that can be stabilized under normal atmospheric conditions – a feat previously limited to a handful of materials like diamond. This breakthrough, published in Nature Communications Chemistry, hinges on a unique approach to material compression and the surprising stability of amorphous structures.
For decades, scientists have sought to “lock in” the unusual atomic arrangements achieved under extreme pressure. Typically, when pressure is released, atoms revert to their stable, low-pressure configurations. However, retaining these high-pressure structures could unlock a new generation of materials with extraordinary properties. “Locking those atomic arrangements in place under ambient conditions could create new classes of useful materials with a wide range of potential applications,” researchers explained.
The key to this discovery lies in shifting the focus from compressing pure carbon dioxide to a mixture of carbon monoxide and oxygen. This seemingly simple change dramatically lowers the pressure required for polymer formation. The team utilized a combination of quantum molecular dynamics simulations and large-scale machine-learning models to predict the optimal pathways for creating the polymer and to understand its behavior under varying conditions. This computational approach allowed for a systematic exploration of pressure and temperature, providing a detailed “recipe” for future experimental work.
“A polymeric form of carbon dioxide stores far more energy than ordinary carbon dioxide because its atoms are locked into a dense, covalently bonded network,” said a senior LLNL scientist. “If such a material can be recovered and stabilized, it represents a high-energy-density material — meaning it can store and potentially release large amounts of energy per unit mass or volume.”
The research team found that starting with a molecular mixture allows transformations to occur at significantly lower pressures – beginning near 7 gigapascals, more than an order of magnitude lower than the over 100 gigapascals previously needed for similar materials. Crucially, this approach favors the formation of amorphous solids, which lack the ordered structure of crystals.
“We believe these amorphous structures experience less bond strain when pressure is released, which enhances their stability under ambient conditions,” the scientist added. “This highlights the potential of amorphous materials – often overlooked in favor of crystals – to offer greater stability and useful properties.”
The stability is attributed to the formation of strong carbon-carbon bonds within the mixture, creating a distinct and robust structure that remains intact even after the pressure is removed. The researchers also provided a physical explanation for why the process works, solidifying the findings.
This work offers a concrete target and strategy for future experimental efforts. Furthermore, the underlying principles could be applied to other light-element systems – involving carbon, oxygen, nitrogen, or hydrogen – potentially leading to entirely new families of recoverable energetic and functional materials.
This research was supported by the LLNL’s Laboratory Directed Research and Development Program.
