American Elements specializes in producing high purity Hafnium Lump with the highest possible density and smallest possible average grain sizes for use in Chemical Vapor Deposition (CVD) and Physical Vapor Deposition (PVD) processes including Thermal and Electron Beam (E-Beam) Evaporation, Low Temperature Organic Evaporation, Atomic Layer Deposition (ALD), Metallic-Organic and Chemical Vapor Deposition (MOCVD). Our standard lump pieces are amorphous uniform pieces in sizes ranging from 5-15 mm. Lump materials are produced using crystallization, solid state and other ultra high purification processes such as sublimation. American Elements specializes in producing custom compositions for commercial and research applications and for new proprietary technologies. American Elements also casts any of the rare earth metals and most other advanced materials into granules, rod, bar or plate form, as well as other machined shapes and through other processes such as nanoparticles (See also application discussion at Nanotechnology Information and at Quantum Dots) and in the form of solutions and organometallics. See research below. We also produce Hafnium as rod, pellets, powder, pieces, granules, ingot, wire, and in compound forms, such as oxide. Other shapes are available by request.
Hafnium is a Block D, Group 4, Period 6 element. The number of electrons in each of Hafnium's shells is 2, 8, 18, 32, 10, 2 and its electronic configuration is [Xe] 4f14 5d2 6s2. In its elemental form hafnium's CAS number is 7440-58-6.The hafnium atom has a radius of 156.4.pm and it's Van der Waals radius is 200.pm. Hafnium is not toxic. Hafnium is one of the Group IV transition elements that is refined from various zirconic mineral deposits. Hafnium is available as metal and compounds with purities from 99% to 99.999% (ACS grade to ultra-high purity); metals in the form of foil, sputtering target, and rod, and compounds as submicron and nanopowder. It's primary uses are due to its ability as a nuclear "getter" or absorber of neutrons. It is a primary component in nuclear control rods for this purpose. It also finds uses as a dopant in the alloy of steel and titanium. It is also used in the production of mantles for high intensity incandescent lamps. Hafnium is replacing polysilicon as the principle gate or electrode material in metaloxide semiconductor field effect transistors (MOSFETs) which are the basis for all modern semiconductors. As semiconductors have gotten smaller, the limiting factor in further size reduction has been the ability of the silicon oxide gate to perform below 10 angstroms where leakage occurs. Recent research has been devoted to the development of High-k materials which can function as a di-electric barrier or gate with lower leakage. Using hafnium based alloys as this di-electric gate has allowed for the development of MOSFET gates smaller than 10 angstroms. This allows for further size reduction, reduced switching power requirements and improved performance. Hafnium was first discovered by Dirk Coster in 1923. See Hafnium research below.
PACKAGING SPECIFICATIONS FOR BULK & RESEARCH QUANTITIES
Typical bulk packaging includes palletized plastic 5 gallon/25 kg. pails, fiber and steel drums to 1 ton super sacks in full container (FCL) or truck load (T/L) quantities. Research and sample quantities and hygroscopic, oxidizing or other air sensitive materials may be packaged under argon or vacuum. Shipping documentation includes a Certificate of Analysis and Material Safety Data Sheet (MSDS). Solutions are packaged in polypropylene, plastic or glass jars up to palletized 440 gallon liquid totes.
N(2) Activation by a Hafnium Complex: A DFT
Study on CO-Assisted Dinitrogen Cleavage and Functionalization. Zhang X, Butschke B, Schwarz H. Chemistry. 2010
Sep 28. [Epub ahead of print] PubMed PMID: 20878807.
Effective enrichment and mass spectrometry analysis of phosphopeptides using
mesoporous metal oxide nanomaterials. Nelson CA, Szczech JR, Dooley CJ, Xu Q, Lawrence MJ, Zhu H, Jin S, Ge Y. Anal Chem. 2010 Sep 1;82(17):7193-201.
PubMed PMID: 20704311; PubMed Central PMCID: PMC2936271.
Synthesis, characterization and
biological study on Cr(3+), ZrO(2+), HfO(2+) and UO(2)(2+) complexes of
oxalohydrazide and bis(3-hydroxyimino)butan-2-ylidene)-oxalohydrazide.
El-Asmy AA, El-Gammal OA, Radwan HA. Spectrochim Acta A Mol Biomol Spectrosc. 2010 Sep 1;76(5):496-501. Epub 2010 Apr
21. PubMed PMID: 20451440.
Intramolecular
sigma-bond metathesis/protonolysis on zirconium(IV) and hafnium(IV) pyridylamido
olefin polymerization catalyst precursors: exploring unexpected reactivity paths.
Luconi L, Giambastiani G, Rossin A, Bianchini C, Lledós A. Inorg Chem. 2010 Aug 2;49(15):6811-3. PubMed PMID: 20583749.
Guided-mode resonant wave plates.
Magnusson R, Shokooh-Saremi M, Johnson EG. Opt Lett. 2010 Jul 15;35(14):2472-4. doi: 10.1364/OL.35.002472. PubMed PMID:
20634867.
Initiation of a
passivated interface between hafnium oxide and In(Ga)As(0 0 1)-(4x2). Clemens JB, Bishop SR, Lee JS, Kummel AC, Droopad R. J Chem
Phys. 2010 Jun 28;132(24):244701. PubMed PMID: 20590208.
Zirconium(IV)- and hafnium(IV)-catalyzed highly
enantioselective epoxidation of homoallylic and bishomoallylic alcohols. Li Z, Yamamoto H. J Am
Chem Soc. 2010 Jun 16;132(23):7878-80. PubMed PMID: 20481541; PubMed Central
PMCID: PMC2886809.
Combined U-Pb and Lu-Hf isotope
analyses by laser ablation MC-ICP-MS: methodology and applications. Matteini M, Dantas EL, Pimentel MM, Bühn B. An Acad Bras
Cienc. 2010 Jun;82(2):479-91. PubMed PMID: 20563428.
Preparation and structures of
enantiomeric dinuclear zirconium and hafnium complexes containing two homochiral
N atoms, and their catalytic property for polymerization of rac-lactide. Hu M, Wang M, Zhu H, Zhang L, Zhang H, Sun L. Dalton
Trans. 2010 May 14;39(18):4440-6. Epub 2010 Mar 31. PubMed PMID: 20358041.
Effect of deposition temperature on the
characteristics of HfN(x) thin films prepared by plasma assisted cyclic chemical
vapor deposition. Kim EJ, Woo HG, Kim DH. J Nanosci Nanotechnol. 2010 May;10(5):3463-6. PubMed PMID:
20358979.
A younger age for ALH84001 and its geochemical link to shergottite sources in
Mars. Lapen TJ, Righter M, Brandon AD, Debaille V, Beard BL, Shafer JT, Peslier AH. Science. 2010 Apr 16;328(5976):347-51. PubMed PMID: 20395507.
Improved reliability from a
plasma-assisted metal-insulator-metal capacitor comprising a high-k HfO2 film on
a flexible polyimide substrate. Meena JS, Chu MC, Kuo SW, Chang FC, Ko FH. Phys Chem Chem Phys. 2010 Mar 20;12(11):2582-9.
Epub 2010 Jan 26. PubMed PMID: 20200734.
Optical coatings in microscale channels by atomic
layer deposition. Gabriel NT, Talghader JJ. Appl Opt. 2010 Mar 10;49(8):1242-8. doi: 10.1364/AO.49.001242.
PubMed PMID: 20220879.
Effect of
TiF4, ZrF4, HfF4 and AmF on erosion and erosion/abrasion of enamel and dentin in
situ. Wiegand A, Hiestand B, Sener B, Magalhães AC, Roos M, Attin T. Arch Oral Biol. 2010 Mar;55(3):223-8. Epub 2010 Jan 18. PubMed PMID:
20083245.
Hydrolysis of
bis(p-nitrophenyl)phosphate by tetravalent metal complexes with Klaui's oxygen
tripodal ligand. Yi XY, Lam TC, Williams ID, Leung WH. Inorg Chem. 2010 Mar 1;49(5):2232-8. PubMed PMID: 20131806.
Synthesis of nested coaxial
multiple-walled nanotubes by atomic layer deposition. Gu D, Baumgart H, Abdel-Fattah TM, Namkoong G. ACS Nano. 2010 Feb
23;4(2):753-8. Erratum in: ACS Nano. 2010 Jul 27;4(7):4331. PubMed PMID:
20085347.
Synthesis and characterisation of ionic liquids based on
1-butyl-3-methylimidazolium chloride and MCl(4), M = Hf and Zr. Campbell PS, Santini CC, Bouchu D, Fenet B, Rycerz L, Chauvin Y, Gaune-Escard
M, Bessada C, Rollet AL. Dalton Trans.
2010 Feb 7;39(5):1379-88. Epub 2009 Dec 1. PubMed PMID: 20104366.
Dielectric
surface-controlled low-voltage organic transistors via n-alkyl phosphonic acid
self-assembled monolayers on high-k metal oxide. Acton BO, Ting GG, Shamberger PJ, Ohuchi FS, Ma H, Jen AK. ACS Appl Mater Interfaces. 2010
Feb;2(2):511-20. PubMed PMID: 20356199.
In situ reaction
mechanism studies on ozone-based atomic layer deposition of Al(2)O(3) and HfO(2). Rose M, Niinistö J, Endler I, Bartha JW, Kücher P, Ritala M.
ACS Appl Mater Interfaces. 2010 Feb;2(2):347-50. PubMed PMID: 20356179.
Is titanium tetrafluoride (TiF4) effective
to prevent carious and erosive lesions? A review of the literature. Wiegand A, Magalhães AC, Attin T. Oral Health
Prev Dent. 2010;8(2):159-64. Review. PubMed PMID: 20589250.