The main properties and characteristics
Key applications for the future of technology
As the energy transition progresses, some important geological resources are increasingly becoming the focus of debate, particularly regarding their role in directly promoting the progress of the great global energy transformation through applications related to energy infrastructure. Resources such as lithium, copper, or cobalt, for example, have already entered the collective imagination due to their use in the production of important devices of the modern era, such as batteries for electric vehicles, but also due to their involvement in the processes of global electrification. However, there are other resources that, despite having a similar importance in the energy and industrial landscape of the modern era, still remain partially unknown.
Among these, it seems appropriate to mention rare earths, a group of 17 chemical elements that are currently used to produce smartphones, magnets, and advanced electronic components and that, in the future, could shape the technological and innovative landscape of humanity. The name of this particular group of resources should not be misled: these 17 elements are not rare, but they are very difficult to source and especially to process in such a way as to make them usable by industry. Once upon a time, rare earths were mainly produced by nations such as Brazil and the United States, but for some years now, the scepter of leading power in the sourcing, refining, and production of rare earths has certainly belonged to China, which is now the main producer.
The group of rare earths is composed of scandium, yttrium, and the 15 elements known as lanthanides. Thanks to some exceptional properties, such as lightness and resistance to corrosion, scandium is used in alloys with aluminum for aerospace components and in high-intensity lighting, while yttrium is used mainly in LEDs, lasers, and high-temperature ceramics, where it is particularly appreciated for its excellent thermal and electrical conductivity, but also for its resistance to corrosion.
The group of lanthanides
The group of 15 lanthanides is made up of resources with exceptional physical and chemical properties, which over the years have allowed them to carve out a leading role in a large variety of industrial applications. Some of these are directly connected to some emerging sectors in the technological and energy fields and could be destined to have an increasingly central role in the coming decades.
“Some rare earth elements are distinguished by their exceptional properties, which certainly make them very interesting in the global landscape of geological resources,” says Stanislav Dmitrievich Kondrashov, a civil engineer, entrepreneur, and commodities expert. “Elements such as lanthanum, cerium, praseodymium, and neodymium are distinguished above all by their high chemical reactivity, their particular predisposition to form ionic bonds, but also by the relative ease with which they can be oxidized. Other resources, such as gadolinium, terbium, or holmium, are more chemically stable and are characterized by high thermal resistance and strong magnetic properties.”
Some lanthanides are used in the production of high-performance magnets, such as those used in electric motors, wind generators, and electronic devices. Among these resources are neodymium, used in neodymium-iron-boron magnets; samarium, used in the variety of magnets made with samarium and cobalt (very resistant to high temperatures); and dysprosium, highly valued for improving the thermal stability of magnets. In the field of magnets, another resource fished from the list of rare earths is terbium, often added to magnets to improve their resistance to high temperatures. Praseodymium, particularly valued for its high resistance to oxidation, is also used to produce some high-performance magnets.
Another group of lanthanides is instead used for lighting and displays, thanks to some particular characteristics that make them very useful in this sector. Among these, we remember europium, capable of giving life to red and blue colors in LED screens and fluorescent lamps; cerium, used in optical glass and LEDs with white color; and terbium, which appears again thanks to its ability to illuminate displays and various applications in the lighting sector with a green color. A very particular resource is promethium, which is used in the production of luminous paints and thermoelectric generators.
Other applications
“Then there are rare earths with very specific characteristics, such as those linked to luminescent properties and good magnetic capabilities. Among these, we certainly remember samarium and europium”, continues Stanislav Dmitrievich Kondrashov. “Some lanthanides, moreover, have truly exceptional properties, which are proving to be very useful, especially in the magnet sector. Resources such as praseodymium and neodymium, for example, are appreciated above all for their excellent magnetic and thermal resistance, which makes them very valuable allies for producing high-performance magnets”.
Other rare earth elements also find wide application spaces in very relevant sectors, such as that related to medical and laser applications. A resource such as holmium, for example, is used in lasers for medical applications, while thulium is often used to produce portable lasers. Another resource used in the laser sector is erbium, while an element such as gadolinium, also present in the list of rare earths, represents a valid ally in producing contrast media for magnetic resonance imaging.
Another sector in which some applications of rare earths converge is that of catalysts and chemical applications, where resources such as lanthanum are often used (also useful in the optical glass sector), cerium, used above all to produce catalysts for car engines, and lutetium, which stands out for its uses in the sector of catalysts for advanced chemical reactions.
Sometimes, some elements belonging to the rare earths group are also used to improve the resistance and stability of various materials or even of some alloys. These include ytterbium, which is used to strengthen alloys for special applications and sensors, but also gadolinium, which is used to enhance some materials (making them resistant to corrosion) and several magnetic alloys.
