Unlocking Promethium: A New Gift from the Titan of Fire, heating up Rare Earth Element Research for Cutting-Edge Technologies
Jürgen Riedel
Innovation Coach helping businesses develop modern strategies using a multi-disciplined approach anchored in GenAI solutions to create trusted businesses | Founder@Baiomics, a DeepTech, ML/AI Tech Consultancy | PhD
The rare earth elements play crucial roles in modern technology, including electronics, clean energy, and various high-tech applications. Their unique electronic, magnetic, and luminescent properties make them indispensable in many advanced materials and technologies. These elements, which include scandium and yttrium along with the 15 lanthanides, are often found together in geological deposits and are similar in their chemical properties [1] . One of the most elusive members is the element promethium.
Promethium, a rare earth element, was discovered in 1945 at Clinton Laboratories (now the Department of Energy’s Oak Ridge National Laboratory, ORNL). It is named after Prometheus, a Titan in Greek religion, known as the supreme trickster and god of fire and famed for his intellect and craftsmanship. Promethium was until now still little studied since it’s discovery over 80 years due to its lack of stable isotopes. A recent study [2] of a multidisciplinary ORNL research team of 18 scientists has elucidate the chemical properties of this last lanthanide bridging a significant gap in lanthanide chemistry essential for modern technological applications. Lanthanides or also called lanthanoids are a series of 15 metallic chemical elements with atomic numbers 57 (lanthanum) through 71 (lutetium). The team successfully prepared a chemical complex of promethium, enabling its first characterization in solution.
The findings significantly enhance the understanding of promethium's chemical bonding properties and its place within the lanthanide series, crucial for the separation and utilization of lanthanides in technologies like lasers, magnets, X-ray screens, and cancer treatment medicines. This research simplifies the separation process of valuable lanthanides and sets a foundation for further exploration of promethium and other rare earth elements, potentially advancing medicine, renewable energy, and space exploration.
Let’s dive deeper into the Properties of Promethium
Promethium's inherent instability due to its lack of stable isotopes has historically hindered in-depth research, with previous studies limited to simple compounds, leaving its coordination chemistry largely unexplored.
A recent study sought to address this knowledge gap by investigating promethium's coordination chemistry and the phenomenon of lanthanide contraction (the decrease in ionic radius across the lanthanide series). Utilizing specialized equipment such as a research reactor, hot cells, and supercomputers, researchers generated enough promethium-147, a specific isotope with a relatively short half-life (the time required for it to reduce to half of its initial value) of 2.62 years to facilitate detailed analysis.
The researchers synthesized a novel ligand to bind promethium in an aqueous solution, enabling the first-ever observation of a promethium complex in solution through advanced techniques like X-ray absorption spectroscopy. This breakthrough not only revealed the complex's structure but also confirmed the predominantly ionic nature of promethium-oxygen bonds, suggesting potential applications in electronics and computing through the design of promethium complexes with tailored properties. Additionally, the study's direct measurements of promethium's chemical properties offered insights into the lanthanide contraction phenomenon. This phenomenon describes the unexpected observation that the atomic and ionic radii of elements within the lanthanide series decrease at a faster rate than would be predicted based solely on the addition of protons to their nuclei.
Computer simulations confirm these experimental findings, further explaining the dynamics of the promethium complex in solution. These combined results hold significant implications for the separation and recovery of promethium and other lanthanides. These elements are crucial for a variety of advanced technologies, including long-lasting nuclear batteries and radiation therapy. Improved understanding of their properties can lead to the development of more efficient and selective extraction and purification methods.
What are the Use Cases for Promethium?
Unlike other lanthanides, promethium is not commonly used in chip production or advanced computing due to its radioactivity and the difficulties involved in handling and integrating it into electronic devices. Its primary applications lie in nuclear batteries, luminescent materials, and specialized research areas. The lack of stable isotopes further limits its suitability for semiconductor technologies, where stability and long-term reliability are paramount.
In contrast, other lanthanides like neodymium, dysprosium, europium, gadolinium, ytterbium, and terbium have significant technological applications. Neodymium and dysprosium are essential for powerful permanent magnets used in computer hard drives, electric vehicle motors, and wind turbines. Europium is crucial for phosphorescent and fluorescent materials in display screens and LEDs. Gadolinium is used in MRI contrast agents and as a neutron absorber in nuclear reactors, while ytterbium and terbium are important for laser technologies and enhancing the performance of electronic devices [2].
Newly discovered properties of promethium suggest potential applications in developing advanced materials for high-performance and quantum computing, where promethium's specific ionic characteristics and stable complexes could be utilized for designing materials with unique magnetic and electronic properties. Additionally, the detailed understanding of promethium's chemical behaviour in aqueous solutions can improve its use in long-life nuclear batteries, radiation therapy, and other advanced technologies, thereby expanding the scope of its technological applications beyond its traditional uses.
领英推荐
A final word on Costs and Environment
The production costs of promethium are high due to the complexities involved in its creation and purification. Promethium is primarily produced through nuclear reactions, a process that involves the irradiation of uranium or plutonium in nuclear reactors, which is inherently complex and expensive. The extraction and purification process is also costly because it requires handling radioactive materials and achieving high purity levels. Furthermore, the scarcity of promethium and the limited number of production facilities available further drive up its production costs.
In contrast, other lanthanides are more cost-effective to produce. Most lanthanides are extracted from minerals such as bastn?site (one of a family of three carbonate-fluoride minerals) and monazite (a primarily reddish-brown phosphate mineral), which are more abundant and less expensive to process compared to synthesizing promethium. Lanthanides are often found together and require separation using well-established techniques like solvent extraction and ion exchange, which are more economical than nuclear synthesis. This leads to market prices for other lanthanides that are generally lower due to their higher natural abundance and more straightforward extraction processes.
Up to now, promethium has had limited value for chip production and advanced computing due to its radioactivity, scarcity, and high production costs. Other lanthanides tend to be highly valuable in these fields due to their essential roles in various electronic components. For instance, neodymium and dysprosium are crucial for high-performance magnets used in electric motors and generators, while europium and terbium are vital for phosphors in displays and lighting. These lanthanides have lower production costs because of their more abundant natural sources and well-established extraction and purification methods.
Besides having many sought-after properties for our high-tech world, lanthanides negatively impact our environment. The extensive and destructive mining and extraction processes can potentially devastate whole ecosystems [3] [4] . There are also political concerns and tensions over who gets access to the precious resources needed to fuel our ever-growing need for AI-driven tech [5] .
The new research into promethium's chemical properties could potentially make its production more cost-effective and environmentally friendly. By elucidating the stable chelation, the formation of multiple coordination bonds between organic molecules and a transition metal ion leading to sequestration of the metal, and coordination chemistry (the study of molecules that poses one or multiple metal centres that is bound to ligands) of promethium in solution, the research enables more efficient extraction and purification processes.
These advancements could reduce the reliance on extensive and destructive mining practices required for other lanthanides, as promethium can be produced in controlled nuclear reactor environments. This method may not only mitigate the environmental impact but also allows for more precise and scalable production, making rare elements like promethium more accessible and sustainable for technological applications. However, this is not to suggest that promethium is the answer to all problems, but the new research suggests that we should invest in research to uncover further properties of lanthanides and perhaps find new alternative materials to replace and even surpass the utility of lanthanides. There is still hope that we will advance our technologies sustainably.
?
References:
Sales Manager
3 个月Lanthanide rare earths. We can provide a large quantity