Each of the rare earth elements has unique chemical, optical, mechanical, electronic, or magnetic properties and can therefore be used in advanced engineering applications such as permanent magnets, luminescent materials, metallurgy, batteries, catalysts, ceramics, pigments, phosphors, nuclear industry, medicine, and nanotechnology.
Schematic illustration of energy storage devices using rare earth element incorporated electrodes including lithium/sodium ion battery, lithium-sulfur battery, rechargeable alkaline battery, supercapacitor, and redox flow battery. Standard redox potential values of rare earth elements.
Rare Earth Oxides are used in mature markets (such as catalysts, glassmaking and metallurgy), which account for 59% of the total worldwide consumption of rare earth elements, and in newer, high-growth markets (such as battery alloys, ceramics, and permanent magnets), which account for 41% of the total worldwide consumption of rare earth elements.
Rare earth compounds directly used as battery electrode material 2.3.1. Rare earth trihydrides Graphite is the mostly used anode for LIBs. The theoretical capacity of graphite is 372 mAh g −1 with voltage plateau around 0 V. It is desired that the capacity of anode would be larger with low voltage plateau.
Rare earth doping in electrode materials The mostly reported RE incorporation in lithium/sodium battery is doping RE elements in the electrode. The lattice of the electrode material will be significantly distorted due to the large ionic radius and complex coordination of RE. Besides, this usually leads to smaller crystallites.
In all kinds of energy storage devices, the most important component is the electrode. Therefore, discovering new electrode material and electrode modification have attracted most of attention of researchers. Rare earth (RE) is a group of VI elements comprised of metals from lanthanum to lutetium .