Yttrium is a silvery transition metal found with rare-earth minerals. It is used in YAG lasers, LED/phosphors (Y2O3:Eu red), high-temperature alloys, ceramics, and superconductors (e.g., YBCO).
Ground-state configuration: \([Kr]4d^1\,5s^2\). Yttrium most commonly forms Y3+ (by losing 3 valence electrons), giving a d^0 ion with chemistry similar to the trivalent lanthanides.
Chemically, Y3+ has an ionic radius and coordination chemistry close to Ln3+ (lanthanides). This similarity stems from the lanthanide contraction, causing Y to co-occur in minerals (e.g., monazite, xenotime) and to be separated with rare-earth processing methods.
YAG is yttrium aluminum garnet with formula \(\mathrm{Y_3Al_5O_{12}}\). When doped with Nd3+, it becomes Nd:YAG, a robust solid-state laser host emitting typically at 1064 nm. Y3+ provides a transparent, mechanically strong lattice while the Nd3+ ions are the active lasing centers.
Red phosphors like Y2O3:Eu3+ or Y2O2S:Eu3+ use Y as a host lattice. The Eu3+ 4f–4f transitions give sharp red emission lines; Y provides chemical/thermal stability and suitable crystal fields for high quantum efficiency.
YBCO (yttrium barium copper oxide) has nominal composition \(\mathrm{YBa_2Cu_3O_{7\! -\! x}}\) and a critical temperature near 92 K (liquid-nitrogen range). Superconductivity arises from CuO2 planes; oxygen stoichiometry (\(x\)) tunes charge carriers and the superconducting phase.
With water (slow at RT, faster when hot):
\(\mathrm{2\,Y + 6\,H_2O \rightarrow 2\,Y(OH)_3 + 3\,H_2\uparrow}\)
With oxygen: forms yttria
\(\mathrm{4\,Y + 3\,O_2 \rightarrow 2\,Y_2O_3}\)
With acids:
\(\mathrm{Y_2O_3 + 6\,HCl \rightarrow 2\,YCl_3 + 3\,H_2O}\)
Ores are digested (acid/alkali), then Y and Ln are separated by solvent extraction or ion exchange using slight differences in Ln/Y complex stabilities. Final products are purified Y2O3 or Y halides, which can be reduced to metal (e.g., Ca reduction of YF3).
Yes. Y-90 is a high-energy beta emitter used in radiotherapy (e.g., radioembolization for liver tumors). Production and use follow strict radiological protocols. Non-radioactive Y compounds are generally of low toxicity but should be handled as fine ceramic/metal powders with dust control.
Metallic Y is a normal paramagnetic metal with good thermal stability. Its significance is as a host or dopant enabling special properties in other materials: superconductivity (YBCO), ionic conductivity (YSZ), photonics (YAG), and luminescence (Y2O3:Eu).