Palladium, Pd

Palladium is a rare and lustrous silvery-white metal that was discovered in 1803 by William Hyde Wollaston, who named it palladium after the asteroid Pallas, which in turn, was named after the epithet of the goddess Athena, acquired by her when she slew the giant Pallas. The symbol for palladium is Pd, and its atomic number is 46. Palladium, along with platinum, rhodium, ruthenium, iridium and osmium form a group of elements referred to as the platinum group metals (PGMs). PGMs share similar chemical properties, but palladium is unique in that it has the lowest melting point and is the least dense of these precious metals. Incredibly, when palladium is at room temperature and atmospheric pressure, it can absorb up to 900 times its own volume of hydrogen, which makes palladium an efficient and safe storage medium for hydrogen and hydrogen isotopes. Palladium is also tarnish resistant, electrically stable and resistant to chemical erosion as well as intense heat.

The unique properties of palladium and other PGMs account for their widespread use. One in four goods manufactured today either contain PGMs or had PGMs play a key role during their manufacturing process. Over half of the supply of palladium and its sister metal platinum goes into catalytic converters, which convert up to 90% of harmful gases from auto exhaust (hydrocarbons, carbon monoxide and nitrogen oxide) into less harmful substances (nitrogen, carbon dioxide and water vapor). Palladium’s precious metal qualities and appearance generate significant consumption in the luxury jewelry market. Palladium is found in many electronics including computers, mobile phones, multi-layer ceramic capacitors, component plating, low voltage electrical contacts, and SED/OLED/LCD televisions. Palladium is also used in dentistry, medicine, hydrogen purification, chemical applications, groundwater treatment, and it plays a key role in the technology used for fuel cells, which combines hydrogen and oxygen to produce electricity, heat and water.

Ore deposits of palladium and other PGMs are rare, and the most extensive deposits have been found in the norite belt of the Bushveld Igneous Complex in the Transvaal in South Africa, the Stillwater Complex in Montana, USA, the Sudbury District of Ontario, Canada, and the Norilsk Complex in Russia. In addition to mining, recycling is also a source of palladium, mostly from scrapped catalytic converters. The numerous applications and limited supply sources of palladium result in palladium drawing considerable investment interest.

Technical Data
Symbol Pd Density (20°C)/gcm3 11.99
Atomic number 46 Melting point / °C 1552
No. of naturally occurring isotopes 6 Boiling point / °C 2940
Atomic weight 106.42 ΔHfus/kJmol-1 17.6(+/-2.1)
Electronic configuration [Kr]4d10 ΔHvap/kJmol-1 362(+/-ll)
Metal radius(12-coordinate)/pm 137 ΔHf(monoatomic gas)/kJmol-1 377(+/-3)
Effective ionic radius(6-coord)/pm IV 61.5 Electrical resistivity  
Effective ionic radius(6-coord)/pm III 76 (20°C)/μohm cm 9.93
Effective ionic radius(6-coord)/pm II 86 Electronegativity χ 2.2
Evaporation Techniques
Temperature (oC) @Vap. Pressure Techniques Remarks
10-8 Torr 10-6 Torr 10-4 Torr Electron Beam Crucible Coil Boat
842 992 1192 Excellent Al2O3 Tungsten Tungsten Alloys with refractory metals; rapid Evaporation suggested. Spits in EB.

Evaporation Materials
P2-5002-M pellets 6mm diameter x 6mm long
P2-5003-M pellets 6mm diameter x 12mm long
P2-5005-M pieces 1-3mm
P2-5009-M pieces 2-8mm

The foils are available in either rectangular or circular shape. Please enter width and length or diameter of the required foil.

Foil
P2-3000-F 0.001" (0.025mm)
P2-3001-F 0.002" (0.050mm)
P2-3003-F 0.004" (0.10mm)
P2-3005-F 0.006" (0.152mm)
P2-3007-F 0.008" (0.20mm)
Powder
P2-10000-P -100 mesh
P2-10001-P -325 mesh
Rods
P2-2000-R 0.0625" (1.58mm)
P2-2001-R 0.125" (3.175mm)
P2-2002-R 0.250" (6.35mm)
P2-2003-R 0.500" (12.7mm)
P2-2004-R 0.625" (15.88mm)
P2-2005-R 0.750" (19.05mm)
P2-2006-R 1" (25.4mm)
Sheet
P2-4001-S 0.015" (0.38mm)
P2-4002-S 0.020" (0.5mm)
P2-4003-S 0.030" (0.76mm)
P2-4004-S 0.040" (1mm)
P2-4006-S 0.060" (1.5mm)
P2-4008-S 0.125" (3.175mm)
P2-4009-S 0.250" (6.35mm)
P2-4010-S 0.375" (9.525mm)
P2-4011-S 0.500" (12.7mm)
P2-4012-S 0.750" (19.05mm)
P2-4013-S 1" (25.4mm)
Wire
P2-1001-W 0.001" (0.025mm)
P2-1002-W 0.002" (0.05mm)
P2-1004-W 0.004" (0.1mm)
P2-1006-W 0.006" (0.152mm)
P2-1008-W 0.008" (0.203mm)
P2-1012-W 0.020" (0.5mm)
P2-1014-W 0.040" (1.0mm)
P2-1018-W 0.080" (2.0mm)