A View from Katherine Bourzac
Skyrocketing Rare Earth Prices and Harnessing Heat
This week’s big materials science stories.
Rare Earth Prices
In the New York Times, Keith Bradsher paints a picture of the troubling economic situation that’s emerging in the rare-earth market. Prices of these metals, which are found in small amounts in a wide range of high-tech products, have been skyrocketing. Manufacturers hope for some relief from new supplies from a processing plant in Malaysia that’s currently under construction. But, Bradsher reports, the Malaysian Atomic Energy Licensing Board has asked its operator, Lynas Corporation of Australia, for additional documentation before approving it. (Rare-earth processing leads to an accumulation of radioactive elements that also occur in the deposits.)
In spite of soaring prices of these elements, the rare-earth supply problems have been invisible to consumers—it hasn’t affected the prices we pay for smartphones, for example. That’s because in most applications of rare earths, only trace amounts are used. That’s not true, though, of electric- and hybrid-car motors or wind turbines. The Prius, for example, uses a kilogram of rare earths. Bradsher notes that while the price of the Prius has gone up, Toyota has attributed this to increased demand for the car, not increased demand for the necessary rare-earth neodymium.
In Science Now, Robert F. Service reports on efforts to do something useful with thermoelectric materials, which can convert heat into electricity. Waste heat is everywhere—car exhaust pipes, computer chips, etc.—and this inefficiency has been tormenting engineers for a long time. But efforts to make use of that waste in materials that can convert heat into electricity haven’t gone very far. Service provides a nice summary of these efforts and explains how researchers have now made one of the most common thermoelectric materials more efficient.