A Brief History of Chemistry and Materials Science Bernard A. Boukamp Inorganic Materials Science AT colloquium, 14 October 2009 Rodin, le Penseur
The three princes of Serendip Serendipity! The king of Serendippo had three sons, which he send out into the world … • They encountered a merchant who has lost a camel • They ask him: • Is he blind on one eye, • Lame • Missing a tooth • Carrying a pregnant woman • Bearing honey on one side • And butter on the other side? • (which turns out to be all correct!)
Materials ‘Science’ … Our far removed ancestors knew how to shape materials and make tools. Bronze age flint arrowhead www.dartfordarchive.org.uk Serendipity?
Technique! Hitting flint stone at an appropriate angle results in a sharp, ‘shell shaped’ edge. www.suffolkcc.gov.uk Stone age ended 6000 – 2500 BC
Bronze age 3000-800 BC transition from stone to bronze for tools & arts N. Afghanistan, 2200-1800 B.C. Bronze: Cu + Sn Tm 950°C Turkey, 3000-2000 B.C.
More complex process, Higher temperature > ~1200°C Reduction of ore with charcoal Obtaining charcoal Bronze age: not only bronze but also gold and silver. Why not iron? Iron is harder than bronze, keeping its cutting edge.
Democritus 460-~370 BC A-tomos On philosophical grounds: There must be a smallest indivisible particle. Arrangement of different particles at micro-scale determine properties at macro-scale.
fire dry hot air earth Aristoteles 384-322 BC wet cold water The four elements from ancient times It started with …
Aristoteles 384-322 BC Science? Founder of Logic and Methodology as tools for Science and Philosophy
Elements recognized in the middle ages. • Metals: • Gold • Silver • Iron • Tin • Mercury • Copper • Lead • Non metals: • Carbon • Sulphur • Antimony Known elements Alchemists: Lead least noble, through transformations to be turned into gold? Important discoveries: 1649 - Hennig Brand: Phosphorous 1766 – Cavendish: Hydrogen gas 1774 – Priestley: Oxygen
1100-1700 Damascener sword Centuries of Materials Science ‘Knowledge’ transferred from father to son, master to apprentice. The art of materials Combination of tough and hard
Newton (by Godfrey Kneller, 1689) Newton published in 1687: ‘Philosphiae Naturalis Principia Mathematica’, Newton ! (1643-1727) … while the alchemists were still in the ‘dark ages’. Origin of classical mechanics Gravitational force Movement of the planets
Grandfather of crystallography Abbé René-Just Haüy (1743-1822) Dropped accidentally a calcite crystal. Saw the same arrangement of ‘side-planes’ in the broken pieces. Deduced from this: ‘molécules intégrates’ as basic building bloc. CaCO3 Essai d'une théorie sur la structure des crystaux (1784)
Steps = smooth? Pyrite or ‘Fools gold’ Not a true five-fold symmetry!!
End of 17th century, begining of 18th: Flogiston? J. J. Becher : In all flammable materials there is present phlogiston, a substance without color, odor, taste, or weight that is given off in burning. “Phlogisticated” substances are those that contain phlogiston and, on being burned, are “dephlogisticated.” The ash of the burned material is held to be the true material. Denounced byA. L. Lavoisier (1743-94) through his research. (But he accepted ‘calorium’ as element.) F.W.J. Schelling (1803): ‘Ist Chemie als Wissenschaft möglich?’
Lavoisier’s ‘calcination’ set-up Bring out the sun! 1743 – 1794 (beheaded by the Guillotine) Prominent tax collector in the ‘Ancient Régime’. Antione Laurent Lavoisier Father of modern chemistry First to formulate conservation law for matter. Observed that oxygen reacted with Cavendish’s ‘burning air’ to form a dew, which Priestly proved to be water. ‘Calcination experiments’
The power of physics Atomic weights early 1800? (trying to get order in the chaos) Dulong and Petit: Potential and kinetic energy = ½ kT / degree of freedom In solid 3 degrees of freedom 3kT energy per atom It follows heat capacitance/mol = 3k x NA = 3R = 25 J/mol.K
1814 1818 1826 Modern O 16 16 16 16 S 32.16 32.19 32.19 32.07 P 26.80 31.88x2 31.38x2 30.98 M 22.33 22.82 -- -- Cl -- -- 35.41 35.46 C 11.99 12.05 12.23 12.01 H 1.062 0.995 0.998 1.008 Atomic weights: more clarity with the help of physics. Berzelius! M = ‘Murium’, an unknown element that, together with oxygen, forms ‘HCl’ (muriatic acid, ‘HMO’).
Sir Humphry Davy (1778-1829) Put electrons to work! Used ‘electrochemistry’ to separate salts. He discovered the alkali metals and many other compounds. Became famous for inventing the mineworkers lamp. He used a ‘white hot gun barrel’ and a Zn/Ag ‘Volta pile’ for the electrolysis of potash, leading to the discovery of Potassium (K)
Regularities in atomic weights Triades !!! 1817: Johann Dobereiner (and others) noticed relations between atomic weights of similar elements: Dumas (1851): N = 14 P = 14+ 17 = 31 As = 14 + 17 + 44 =75 Sb = 14 + 17 + 88 = 119 Bi = 14 + 17 + 176 = 207 Li = 7 Na = 7 + 16 = 23 K = 23 + 16 = 39 Mg = 12 Ca = 12 + 8 =20 Sr = 20 + 24 = 44 Ba = 44 + 24 = 68 Also ‘lateral relations’ were observed: Cl - P = Br - As = I - Sb = 5 This led eventually to …
Mendeleèff Start of the modern Periodic Table Mendeleev and simultaneously Meyers: ordening according to atomic weights and similar properties. Based on his system Mendeleev did correct predictions of still unknown, missing elements.
The original Atomic weights, not atomic numbers!
The Spectroscopists Advances in understanding Robert Wilhelm Bunsen and Robert Gustav Kirchoff developed the spectrograph (1860), based on the colourless (!) Bunsen burner. Many new elements were discovered based on their unique emission spectra. Within a few month cesium and rubidium were discovered. R.W. Bunsen
H-spectrum Emission spectrum of hydrogen S = Scharf P = Prinzpal D = Diffuse F = Feinstruktuur
19th Century Meanwhile demands of society on materials grew: Bigger, larger, faster …. But materials science was still largely empirical.
The era of steam … Factories, commerce, travel … placed ever increasing demands on iron Fundamental knowledge of iron & steel? The “Firth of Forth” Bridge, 2.5 km. Built from 1883-1890.
While in Paris Construction of the Eiffeltower. World exhibition 1889.
Enigma? Work hardening & strength. On ‘theoretical’ grounds: Force to deform metals 100 – 1000 times higher than in practice!
Postulate: dislocations! Vito Volterra, 1860-1940 Mathematician / physicist 1905: theory of dislocations in crystals. Volterra’s dislocation models
Real dislocations Deformation by stepwise moving of a half-plane
Influence % carbon on brittleness. Second World War (1940 - 1945) Lack of understanding ‘Liberty Ships’ cracked in the Northern Ice Sea
Wilhelm Conrad Röntgen Discovered the ‘Röntgen’ rays in 1895.Named these ‘X=rays’. Invisible rays Nobel prize 1901 Radiation went straight through a closed, black carton, hitting a fluorescent screen.
Red Beryl Beryl: Al2Be3Si6O18 Modern ‘Laue diagram’, using ‘white radiation’. Enigma: ‘X-rays’ could not be diffracted by regular grids. Max von Laue Nobel prize 1914 Max von Laue assumed the ‘X-ray’ wavelength to be in the order of atom-atom distances in a crystal.
Sir William Henry Bragg: He saw the shortcomings of the Von Laue method. His solution: rotating single crystal. Bragg’s law Noble prize 1915! Conditions for reflection: The most important thing in science is not so much to obtain new facts as to discover new ways of thinking about them.
From art to science Materials science became a real science due to the development of modern analysis and imaging techniques. Modern analysis and imaging techniques become possible due to developments in the materials science …… Turn of the century
1890-1900 Microscopes! • 1931 Max Knoll and Ernst Ruska • build first electron microscope • 1933 Ruska developes an EM with • higher resolution than an optical • microscope • 1937 The first scanning electron • microscope is built • 1939 Siemens brings the first • commercial EM on the market • 1965 First commercial SEM (Oatley)
Beyond our imagination Impact of high resolution microscopic images. Tremendous depth of sharpness!
Max Planck (1858-1947) quantum theory: E = h 1913 Niels Bohr ‘electron orbits’, Explanation of principal quantum numbers, n = 1, 2, 3 .. and lines prectrum of H and He+ Enter the physics! Quantum mechanics provided a consistent theory Linus Pauling (Cal. Tech), on a study tour in Europe, used quantum mechanics to explain the chemical bond: ‘The Nature of the Chemical Bond’ (1939). And chemistry became a real science. • Pauling visited in Europe: • Louis de Broglie • Erwin Schrödinger • Wolfgang Pauli • Paul Dirac • Max Born • Walter Heitler • Fritz London
Greatest impact from/on materials science? Start of the Silicon age! 23 December 1947. Brattain and Bardeen’s pnp pointcontact germanium transistor workt as an 18-times amplifier! Nobel prize 1956
Postulated in 1965 ! www.intel.com/research/silicon/mooreslaw.htm Where are we going now? Quest for nano! • Electronics require ever smaller structures (Moore’s law): • more transistors, higher frequencies • new lithography techniques! • self assembling structures = nano !
Graphite silicium The ultimate tool • Atoms become visible! • 1982 - Scanning Tunneling Microscope • Gerd Binnig (IBM) • 1986 - Atomic Force Microscope • Uses van der Waals Force • All materials surfaces can be studied. One can drag atoms across the surface, Make new compounds, Infinite possibilities!
Conclusion Expect the unexpected Look for the details Have an open mind Science is still a great adventure Thanks for your kind attention