Hafnium information, including Technical Data, Safety Data and its high purity properties, research, applications and other useful facts are discussed below. Scientific facts such as the atomic structure, ionization energy, abundance on Earth, conductivity and thermal properties are included.
 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 metal oxide 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 facts, including appearance, CAS #, and molecular formula and safety data, research and properties are
available for many specific states, forms and shapes on the product pages listed to the left. Elemental or metallic forms include pellets, rod, wire and granules for evaporation source material purposes. Nanoparticles and nanopowders provide ultra high surface area which nanotechnology research and recent experiments demonstrate function to create new and unique properties and benefits.
 Oxides are available in forms including powders and dense pellets for such uses as optical coating and thin film applications. Oxides tend to be insoluble. Fluorides are another insoluble form for uses in which oxygen is undesirable such as metallurgy, chemical and physical vapor deposition and in some optical coatings. Hafnium is available in soluble forms including chlorides, nitrates and acetates. These compounds are also manufactured as solutions at specified stoichiometries.
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.
All elemental metals, compounds and solutions may be synthesized in ultra high purity (e.g. 99.999%) for laboratory standards, advanced electronic, thin fillm deposition using sputtering targets and evaporation materials, metallurgy and optical materials and other high technology applications. Information is provided for stable (non-radioactive) isotopes. Organo-Metallic Hafnium compounds are soluble in organic or non-aqueous solvents. See Analytical Services for information on available certified chemical and physical analysis techniques including MS-ICP, X-Ray Diffraction, PSD and Surface Area (BET) analysis.
Hafnium was first discovered by Dirk Coster in 1923.
 hafnium |
 Hafnium |
 afnio |
 Háfnio |
 hafnio |
 Hafnium |
Abundance. The following table shows the abundance of hafnium and each of its naturally occurring isotopes on Earth along with the atomic mass for each isotope.
| Isotope |
Atomic Mass |
% Abundance on Earth |
| Hf-174 |
173.940040 |
0.162 |
| Hf-176 |
175.941402 |
5.206 |
| Hf-177 |
176.943220 |
18.606 |
| Hf-178 |
177.943698 |
27.297 |
| Hf-179 |
178.945815 |
13.629 |
| Hf-180 |
179.946549 |
35.100 |
The following table shows the abundance of Hafnium present in the human body and in the universe scaled to parts per billion (ppb) by weight and by atom:
| |
Typical Human Body |
Universe |
| by Weight |
no data |
0.7 ppb |
| by Atom |
no data |
0.005 ppb |
Safety Data and Biological Role. The safety data for hafnium metal, nanoparticles and its compounds can vary widely depending on the form. For potential hazard information, toxicity, and road, sea and air transportation limitations, such as DOT Hazard Class, DOT Number, EU Number, NFPA Health rating and RTECS Class, please see the specific material or compound referenced in the left margin. Hafnium compounds have no biological role.
Ionization Energy. The ionization energy for hafnium (the least required energy to release a single electron from the atom in it's ground state in the gas phase) is stated in the following table:
| 1st Ionization Energy |
658.52 kJ mol-1 |
| 2nd Ionization Energy |
1437.64 kJ mol-1 |
| 3rd Ionization Energy |
2248.12 kJ mol-1 |
Conductivity. As to hafnium's electrical and thermal conductivity, the electrical conductivity measured as to electrical resistivity @ 20 ºC is 33.08 μΩcm and its electronegativities (or its ability to draw electrons relative to other elements) is 1.3. The thermal conductivity of hafnium is 23 W m-1 K-1.
Thermal Properties. The melting point and boiling point for hafnium are stated below. The following chart sets forth the heat of fusion, heat of vaporization and heat of atomization.
| Heat of Fusion |
25.5 kJ mol-1 |
| Heat of Vaporization |
570.7 kJ mol-1 |
| Heat of Atomization |
618.9 kJ mol-1 |
Recent Research & Development for HafniumCharacterization of the SnO2 based thin film transistors with Ga, In and Hf doping.
Shin SY, Moon YK, Kim WS, Lee SH, Park JW.
J Nanosci Nanotechnol. 2012 Jul;12(7):5459-63.
PMID:
22966590
[PubMed - in process]
Zirconium((IV)) and Hafnium((IV)) Porphyrin and Phthalocyanine Complexes as New Dyes for Solar Cell Devices.
Radivojevic I, Bazzan G, Burton-Pye BP, Ithisuphalap K, Saleh R, Durstock MF, Francesconi LC, Drain CM.
J Phys Chem C Nanomater Interfaces. 2012 Aug 2;116(30):15867-15877. Epub 2012 Jun 26.
PMID:
22962625
[PubMed]
Ring opening polymerization of rac-lactide by group 4 tetracarbamato complexes: activation, propagation and role of the metal.
Marchetti F, Pampaloni G, Pinzino C, Renili F, Repo T, Vuorinen S.
Dalton Trans. 2012 Sep 7. [Epub ahead of print]
PMID:
22960935
[PubMed - as supplied by publisher]
Density of States-Based Design of Metal Oxide Thin-Film Transistors for High Mobility and Superior Photostability.
Kim HS, Park JS, Jeong HK, Son KS, Kim TS, Seon JB, Lee E, Chung JG, Kim DH, Ryu M, Lee SY.
ACS Appl Mater Interfaces. 2012 Sep 19. [Epub ahead of print]
PMID:
22957907
[PubMed - as supplied by publisher]
Immobilization Mechanisms of Deoxyribonucleic Acid (DNA) to Hafnium Dioxide (HfO(2)) Surfaces for Biosensing Applications.
Fahrenkopf NM, Rice PZ, Bergkvist M, Deskins NA, Cady NC.
ACS Appl Mater Interfaces. 2012 Sep 21. [Epub ahead of print]
PMID:
22947770
[PubMed - as supplied by publisher]
O-vacancies in (i) nano-crystalline HfO2 and (i) non-crystalline SiO2 and Si3N4 studied by X-ray absorption spectroscopy.
Lucovsky G, Miotti L, Bastos KP.
J Nanosci Nanotechnol. 2012 Jun;12(6):4811-9.
PMID:
22905534
[PubMed - indexed for MEDLINE]
Nano-hardness, wear resistance and pseudoelasticity of hafnium implanted NiTi shape memory alloy.
Zhao T, Li Y, Liu Y, Zhao X.
J Mech Behav Biomed Mater. 2012 Apr 25;13C:174-184. [Epub ahead of print]
PMID:
22902997
[PubMed - as supplied by publisher]
Zirconia implant abutments: microstructural analysis.
Vaquero-Aguilar C, Jimenez-Melendo M, Torres-Lagares D, Llena-Blasco O, Bruguera A, Llena-Blasco J, Garcia-Calderon M, Velazquez-Cayon R, Gutierrez-Perez JL.
Int J Oral Maxillofac Implants. 2012 Jul;27(4):785-91.
PMID:
22848879
[PubMed - in process]
Insight into the electronic structure, optical properties, and redox behavior of the hybrid phthalocyaninoclathrochelates from experimental and density functional theory approaches.
Sabin JR, Varzatskii OA, Voloshin YZ, Starikova ZA, Novikov VV, Nemykin VN.
Inorg Chem. 2012 Aug 6;51(15):8362-72. Epub 2012 Jul 16.
PMID:
22800298
[PubMed - in process]
Multifunctional phosphonic acid self-assembled monolayers on metal oxides as dielectrics, interface modification layers and semiconductors for low-voltage high-performance organic field-effect transistors.
Ma H, Acton O, Hutchins DO, Cernetic N, Jen AK.
Phys Chem Chem Phys. 2012 Jul 6. [Epub ahead of print]
PMID:
22767209
[PubMed - as supplied by publisher]
Silicon nanowires with high-k hafnium oxide dielectrics for sensitive detection of small nucleic acid oligomers.
Dorvel BR, Reddy B Jr, Go J, Duarte Guevara C, Salm E, Alam MA, Bashir R.
ACS Nano. 2012 Jul 24;6(7):6150-64. Epub 2012 Jun 22.
PMID:
22695179
[PubMed - in process]
Synthesis and structure of amido- and imido(pentafluorophenyl)borane zirconocene and hafnocene complexes: N-H and B-H activation.
Jacobs EA, Fuller A, Coles SJ, Jones GA, Tizzard GJ, Wright JA, Lancaster SJ.
Chemistry. 2012 Jul 9;18(28):8647-58. doi: 10.1002/chem.201200704. Epub 2012 Jun 12.
PMID:
22692881
[PubMed - in process]
Hafnium isotope evidence for a transition in the dynamics of continental growth 3.2 Gyr ago.
Næraa T, Scherstén A, Rosing MT, Kemp AI, Hoffmann JE, Kokfelt TF, Whitehouse MJ.
Nature. 2012 May 30;485(7400):627-30. doi: 10.1038/nature11140.
PMID:
22660324
[PubMed]
Synthesis, characterization, and lactide polymerization activity of group 4 metal complexes containing two bis(phenolate) ligands.
Sauer A, Buffet JC, Spaniol TP, Nagae H, Mashima K, Okuda J.
Inorg Chem. 2012 May 21;51(10):5764-70. Epub 2012 May 9.
PMID:
22571415
[PubMed - indexed for MEDLINE]
Characterization of multi-principal-element (TiZrNbHfTa)N and (TiZrNbHfTa)C coatings for biomedical applications.
Braic V, Balaceanu M, Braic M, Vladescu A, Panseri S, Russo A.
J Mech Behav Biomed Mater. 2012 Jun;10:197-205. Epub 2012 Mar 3.
PMID:
22520431
[PubMed - indexed for MEDLINE]
Photoelectron spectroscopy of the molecular anions, ZrO-, HfO-, HfHO-, and HfO2H-.
Li X, Zheng W, Buonaugurio A, Buytendyk A, Bowen K, Balasubramanian K.
J Chem Phys. 2012 Apr 21;136(15):154306.
PMID:
22519325
[PubMed]
Low-voltage bendable pentacene thin-film transistor with stainless steel substrate and polystyrene-coated hafnium silicate dielectric.
Yun DJ, Lee S, Yong K, Rhee SW.
ACS Appl Mater Interfaces. 2012 Apr;4(4):2025-32. Epub 2012 Apr 10.
PMID:
22462593
[PubMed - in process]
Quantum cascade laser-based measurement of metal alkylamide density during atomic layer deposition.
Maslar JE, Kimes WA, Sperling BA.
Appl Spectrosc. 2012 Mar;66(3):324-33.
PMID:
22449311
[PubMed]
A change in the geodynamics of continental growth 3 billion years ago.
Dhuime B, Hawkesworth CJ, Cawood PA, Storey CD.
Science. 2012 Mar 16;335(6074):1334-6.
PMID:
22422979
[PubMed]
Hf(IV)-catalyzed enantioselective epoxidation of N-alkenyl sulfonamides and N-tosyl imines.
Olivares-Romero JL, Li Z, Yamamoto H.
J Am Chem Soc. 2012 Mar 28;134(12):5440-3. Epub 2012 Mar 20.
PMID:
22420598
[PubMed - indexed for MEDLINE] |
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