Triboluminescence

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Triboluminescence of nicotine L-salicylate

Triboluminescence is a phenomenon in which light is generated when a material is mechanically pulled apart, ripped, scratched, crushed, or rubbed (see tribology). The phenomenon is not fully understood but appears in most cases to be caused by the separation and reunification of static electric charges, see also triboelectric effect. The term comes from the Greek τρίβειν ("to rub"; see tribology) and the Latin lumen (light). Triboluminescence can be observed when breaking sugar crystals and peeling adhesive tapes.

Contents

Triboluminescence is often a synonym for fractoluminescence (a term mainly used when referring only to light emitted from fractured crystals). Triboluminescence differs from piezoluminescence in that a piezoluminescent material emits light when deformed, as opposed to broken. These are examples of mechanoluminescence, which is luminescence resulting from any mechanical action on a solid.

History

An Uncompahgre Ute Buffalo rawhide ceremonial rattle filled with quartz crystals. Flashes of light are visible when the quartz crystals are subjected to mechanical stress in darkness. UteQuartzRattle.jpg
An Uncompahgre Ute Buffalo rawhide ceremonial rattle filled with quartz crystals. Flashes of light are visible when the quartz crystals are subjected to mechanical stress in darkness.

Quartz rattlers of the Uncompahgre Ute indigenous people

The Uncompahgre Ute indigenous people from Central Colorado are one of the first documented groups of people in the world credited with the application of mechanoluminescence involving the use of quartz crystals to generate light. [1] [2] The Ute constructed unique ceremonial rattles made from buffalo rawhide which they filled with clear quartz crystals collected from the mountains of Colorado and Utah. When the rattles were shaken at night during ceremonies, the friction and mechanical stress of the quartz crystals impacting together produced flashes of light visible through the translucent buffalo hide.

Early scientific reports

The first recorded observation is attributed to English scholar Francis Bacon when he recorded in his 1620 Novum Organum that "It is well known that all sugar, whether candied or plain, if it be hard, will sparkle when broken or scraped in the dark." [3] The scientist Robert Boyle also reported on some of his work on triboluminescence in 1663. [4] In 1675. Astronomer Jean-Felix Picard observed that his barometer was glowing in the dark as he carried it. His barometer consisted of a glass tube that was partially filled with mercury. The empty space above the mercury would glow whenever the mercury slid down the glass tube. [5]

In the late 1790s, sugar production began to produce more refined sugar crystals. These crystals were formed into a large solid cone for transport and sale. This solid sugar cone had to be broken into usable chunks using a sugar nips device. People began to notice that tiny bursts of light were visible as sugar was "nipped" in low light, an established example of triboluminescence. [6]

Mechanism of action

There remain a few ambiguities about the effect. The current theory of triboluminescence—based upon crystallographic, spectroscopic, and other experimental evidence—is that upon fracture of asymmetrical materials, charge is separated. When the charges recombine, the electrical discharge ionizes the surrounding air, causing a flash of light. Research further suggests that crystals that display triboluminescence often lack symmetry and are poor conductors. [7] However, there are substances which break this rule, and which do not possess asymmetry, yet display triboluminescence, such as hexakis(antipyrine)terbium iodide. [8] It is thought that these materials contain impurities, which make the substance locally asymmetric. Further information on some of the possible processes involved can be found in the page on the triboelectric effect.

The biological phenomenon of triboluminescence is thought to be controlled by recombination of free radicals during mechanical activation. [9]

Examples

In common materials

Triboluminescence in quartz

Certain household materials and substances can be seen to exhibit the property:

A diamond may begin to glow while being rubbed; this occasionally happens to diamonds while a facet is being ground or the diamond is being sawn during the cutting process. Diamonds may fluoresce blue or red. Some other minerals, such as quartz, are triboluminescent, emitting light when rubbed together. [19]

Triboluminescence as a biological phenomenon is observed in mechanical deformation and contact electrification of epidermal surface of osseous and soft tissues, during chewing food, at friction in joints of vertebrae, during sexual intercourse, and during blood circulation. [20] [21]

Water jet abrasive cutting of ceramics (e.g., tiles) creates a yellow/orange glow at the point of impact of very high-speed flow.

Chemicals notable for their triboluminescence

Fractoluminescence

Fractoluminescence is often used as a synonym for triboluminescence. [27] It is the emission of light from the fracture (rather than rubbing) of a crystal, but fracturing often occurs with rubbing. Depending upon the atomic and molecular composition of the crystal, when the crystal fractures, a charge separation can occur, making one side of the fractured crystal positively charged and the other side negatively charged. Like in triboluminescence, if the charge separation results in a large enough electric potential, a discharge across the gap and through the bath gas between the interfaces can occur. The potential at which this occurs depends upon the dielectric properties of the bath gas. [28]

EMR propagation during fracturing

The emission of electromagnetic radiation (EMR) during plastic deformation and crack propagation in metals and rocks has been studied. The EMR emissions from metals and alloys have also been explored and confirmed. Molotskii presented a dislocation mechanism for this type of EMR emission. [29] In 2005, Srilakshmi and Misra reported an additional phenomenon of secondary EMR during plastic deformation and crack propagation in uncoated and metal-coated metals and alloys. [30]

EMR during the micro-plastic deformation and crack propagation from several metals and alloys and transient magnetic field generation during necking in ferromagnetic metals were reported by Misra (1973–75), which have been confirmed and explored by several researchers. [31] Tudik and Valuev (1980) were able to measure the EMR frequency during tensile fracture of iron and aluminum in the region 100 THz by using photomultipliers. Srilakshmi and Misra (2005a) also reported an additional phenomenon of secondary electromagnetic radiation in uncoated and metal-coated metals and alloys. If a solid material is subjected to stresses of large amplitudes, which can cause plastic deformation and fracture, emissions such as thermal, acoustic, ions, and exo-emissions occur.

Deformation induced EMR

The study of deformation is essential for the development of new materials. Deformation in metals depends on temperature, type of stress applied, strain rate, oxidation, and corrosion. Deformation-induced EMR can be divided into three categories: effects in ionic crystal materials, effects in rocks and granites, and effects in metals and alloys. EMR emission depends on the orientation of the grains in individual crystals since material properties are different in differing directions. [32] Amplitude of the EMR pulse increases as long as the crack grows as new atomic bonds are broken, leading to EMR. The Pulse starts to decay as the cracking halts. [33] Observations from experiments showed that emitted EMR signals contain mixed frequency components.

Test methods to measure EMR

The most widely used tensile test method is used to characterize the mechanical properties of materials. From any complete tensile test record, one can obtain important information about the material's elastic properties, the character and extent of plastic deformation, yield, and tensile strengths and toughness. The information obtained from one test justifies the extensive use of tensile tests in engineering materials research. Therefore, investigations of EMR emissions are mainly based on the tensile test of the specimens. From experiments, it can be shown that tensile crack formation excites more intensive EMR than shear cracking, increasing the elasticity, strength, and loading rate during uniaxial loading increases amplitude. Poisson's ratio is a key parameter for EMR characterization during triaxial compression. [34] If the Poisson's ratio is lower, it is harder for the material to strain transversally and hence there is a higher probability of new fractures.

See also

Related Research Articles

<span class="mw-page-title-main">Electromagnetic radiation</span> Waves of the electromagnetic field

In physics, electromagnetic radiation (EMR) consists of waves of the electromagnetic (EM) field, which propagate through space and carry momentum and electromagnetic radiant energy. Types of EMR include radio waves, microwaves, infrared, (visible) light, ultraviolet, X-rays, and gamma rays, all of which are part of the electromagnetic spectrum.

<span class="mw-page-title-main">Light</span> Electromagnetic radiation humans can see

Light or visible light is electromagnetic radiation that can be perceived by the human eye. Visible light is usually defined as having wavelengths in the range of 400–700 nanometres (nm), corresponding to frequencies of 750–420 terahertz, between the infrared and the ultraviolet.

<span class="mw-page-title-main">Luminescence</span> Spontaneous emission of light by a substance

Luminescence is the "spontaneous emission of radiation from an electronically excited species not in thermal equilibrium with its environment", according to the IUPAC definition.  A luminescent object is emitting "cold light", in contrast to "incandescence", where an object only emits light after heating. Generally, the emission of light is due to the movement of electrons between different energy levels within an atom after excitation by external factors. However, the exact mechanism of light emission in "vibrationally excited species" is unknown, as seen in sonoluminescence.

<span class="mw-page-title-main">Cathodoluminescence</span> Photon emission under the impact of an electron beam

Cathodoluminescence is an optical and electromagnetic phenomenon in which electrons impacting on a luminescent material such as a phosphor, cause the emission of photons which may have wavelengths in the visible spectrum. A familiar example is the generation of light by an electron beam scanning the phosphor-coated inner surface of the screen of a television that uses a cathode ray tube. Cathodoluminescence is the inverse of the photoelectric effect, in which electron emission is induced by irradiation with photons.

<span class="mw-page-title-main">Ductility</span> Degree to which a material under stress irreversibly deforms before failure

Ductility is a mechanical property commonly described as a material's amenability to drawing. In materials science, ductility is defined by the degree to which a material can sustain plastic deformation under tensile stress before failure. Ductility is an important consideration in engineering and manufacturing. It defines a material's suitability for certain manufacturing operations and its capacity to absorb mechanical overload. Some metals that are generally described as ductile include gold and copper, while platinum is the most ductile of all metals in pure form. However, not all metals experience ductile failure as some can be characterized with brittle failure like cast iron. Polymers generally can be viewed as ductile materials as they typically allow for plastic deformation.

<span class="mw-page-title-main">Fracture</span> Split of materials or structures under stress

Fracture is the appearance of a crack or complete separation of an object or material into two or more pieces under the action of stress. The fracture of a solid usually occurs due to the development of certain displacement discontinuity surfaces within the solid. If a displacement develops perpendicular to the surface, it is called a normal tensile crack or simply a crack; if a displacement develops tangentially, it is called a shear crack, slip band, or dislocation.

<span class="mw-page-title-main">Phosphorescence</span> Process in which energy absorbed by a substance is released relatively slowly in the form of light

Phosphorescence is a type of photoluminescence related to fluorescence. When exposed to light (radiation) of a shorter wavelength, a phosphorescent substance will glow, absorbing the light and reemitting it at a longer wavelength. Unlike fluorescence, a phosphorescent material does not immediately reemit the radiation it absorbs. Instead, a phosphorescent material absorbs some of the radiation energy and reemits it for a much longer time after the radiation source is removed.

<span class="mw-page-title-main">Scintillator</span> Material which glows when excited by ionizing radiation

A scintillator is a material that exhibits scintillation, the property of luminescence, when excited by ionizing radiation. Luminescent materials, when struck by an incoming particle, absorb its energy and scintillate. Sometimes, the excited state is metastable, so the relaxation back down from the excited state to lower states is delayed. The process then corresponds to one of two phenomena: delayed fluorescence or phosphorescence. The correspondence depends on the type of transition and hence the wavelength of the emitted optical photon.

In chemistry, chromism is a process that induces a change, often reversible, in the colors of compounds. In most cases, chromism is based on a change in the electron states of molecules, especially the π- or d-electron state, so this phenomenon is induced by various external stimuli which can alter the electron density of substances. It is known that there are many natural compounds that have chromism, and many artificial compounds with specific chromism have been synthesized to date. It is usually synonymous with chromotropism, the (reversible) change in color of a substance due to the physical and chemical properties of its ambient surrounding medium, such as temperature and pressure, light, solvent, and presence of ions and electrons.

<span class="mw-page-title-main">Work hardening</span> Strengthening a material through plastic deformation

In materials science, work hardening, also known as strain hardening, is the strengthening of a metal or polymer by plastic deformation. Work hardening may be desirable, undesirable, or inconsequential, depending on the context.

<span class="mw-page-title-main">Residual stress</span> Stresses which remain in a solid material after the original cause is removed

In materials science and solid mechanics, residual stresses are stresses that remain in a solid material after the original cause of the stresses has been removed. Residual stress may be desirable or undesirable. For example, laser peening imparts deep beneficial compressive residual stresses into metal components such as turbine engine fan blades, and it is used in toughened glass to allow for large, thin, crack- and scratch-resistant glass displays on smartphones. However, unintended residual stress in a designed structure may cause it to fail prematurely.

<span class="mw-page-title-main">Strontium aluminate</span> Chemical compound

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<span class="mw-page-title-main">Embrittlement</span> Loss of ductility of a material, making it brittle

Embrittlement is a significant decrease of ductility of a material, which makes the material brittle. Embrittlement is used to describe any phenomena where the environment compromises a stressed material's mechanical performance, such as temperature or environmental composition. This is oftentimes undesirable as brittle fracture occurs quicker and can much more easily propagate than ductile fracture, leading to complete failure of the equipment. Various materials have different mechanisms of embrittlement, therefore it can manifest in a variety of ways, from slow crack growth to a reduction of tensile ductility and toughness.

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Piezoluminescence is a form of luminescence created by pressure upon certain solids. This phenomenon is characterized by recombination processes involving electrons, holes and impurity ion centres. Some piezoelectric crystals give off a certain amount of piezoluminescence when under pressure. Irradiated salts, such as NaCl, KCl, KBr and polycrystalline chips of LiF (TLD-100), have been found to exhibit piezoluminescent properties. It has also been discovered that ferroelectric polymers exhibit piezoluminescence upon the application of stress.

In materials science, toughening refers to the process of making a material more resistant to the propagation of cracks. When a crack propagates, the associated irreversible work in different materials classes is different. Thus, the most effective toughening mechanisms differ among different materials classes. The crack tip plasticity is important in toughening of metals and long-chain polymers. Ceramics have limited crack tip plasticity and primarily rely on different toughening mechanisms.

References

  1. ↑ "BBC Big Bang on triboluminescence". Archived from the original on 2019-12-21. Retrieved 2019-12-25.
  2. ↑ Dawson, Timothy (2010). "Changing colors: now you see them, now you don't". Coloration Technology. 126 (4): 177–188. doi:10.1111/j.1478-4408.2010.00247.x.
  3. ↑ Bacon, Francis. Novum Organum Archived 2006-05-03 at the Wayback Machine
  4. ↑ Boyle, Robert (1663). "A COPY OF THE LETTER That Mr. Boyle wrote to Sir Robert Morray, to accompany the Observations touch∣ing the Shining Diamond". Experiments and considerations touching colours first occasionally written, among some other essays to a friend, and now suffer'd to come abroad as the beginning of an experimental history of colours. pp. 391–411.
  5. ↑ (Staff) (1676). "Experience faire à l'Observatoire sur la Barometre simple touchant un nouveau Phenomene qu'on y a découvert" [Experiment done at the [Paris] observatory on a simple barometer concerning a new phenomenon that was discovered there]. Journal des Sçavans (Paris edition) (in French): 112–113.
  6. ↑ Wick, Frances G. (1940). "Triboluminescence of Sugar". JOSA. 30 (7): 302–306. doi:10.1364/JOSA.30.000302.
  7. ↑ Fontenot, R. S.; Bhat, K. N.; Hollerman, W. A.; Aggarwal, M. D.; Nguyen, K. M. (2012). "Comparison of the triboluminescent yield and decay time for europium dibenzoylmethide triethylammonium synthesized using different solvents". CrystEngComm. Royal Society of Chemistry (RSC). 14 (4): 1382–1386. doi:10.1039/c2ce06277a. ISSN   1466-8033.
  8. ↑ W. Clegg, G. Bourhill and I. Sage (April 2002). "Hexakis(antipyrine-O)terbium(III) triiodide at 160 K: confirmation of a centrosymmetric structure for a brilliantly triboluminescent complex". Acta Crystallographica Section E. 58 (4): m159–m161. doi: 10.1107/S1600536802005093 .
  9. ↑ Orel, V.E.; Alekseyev, S.B.; Grinevich, Yu.A. (1992), "Mechanoluminescence: an assay for lymphocyte analysis in neoplasis", Bioluminescence and Chemiluminescence, 7 (4): 239–244, doi:10.1002/bio.1170070403, PMID   1442175
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  13. ↑ Chang, Kenneth (2008-10-23). "Scotch Tape Unleashes X-Ray Power". The New York Times. Archived from the original on 2017-09-30. Retrieved 2017-02-25.
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  15. ↑ Krishna, G N; Chowdhury, S.K.Roy; Biswas, A. (2014). "X-Ray Emission during Rubbing of Metals" (PDF). Tribology in Industry. 36 (3): 229–235. ProQuest   2555415391.
  16. ↑ Alexander, Andrew J. (5 September 2012). "Interfacial Ion-Transfer Mechanism for the Intense Luminescence Observed When Opening Self-Seal Envelopes". Langmuir. American Chemical Society (ACS). 28 (37): 13294–13299. doi:10.1021/la302689y. hdl: 20.500.11820/78782d2a-b87f-4fda-813c-6a282d1fd9c6 . ISSN   0743-7463. PMID   22924818. S2CID   32480331.
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  19. ↑ "Rockhounding Arkansas: Experiments with Quartz". Rockhoundingar.com. Archived from the original on 2012-04-24. Retrieved 2012-10-09.
  20. ↑ Orel, V.E. (1989). Triboluminescence as a biological phenomenion and methods for its investigation. Biological luminescence : proceedings of the first international school, Książ Castle, Wrocław, Poland, June 20-23, 1989 (in 131-147). Singapore: World Scientific. doi:10.13140/RG.2.1.2298.5443. ISBN   9789810204051.{{cite book}}: CS1 maint: unrecognized language (link)
  21. ↑ Orel, Valeri E.; Alekseyev, Sergei B.; Grinevich, Yuri A. (October 1992). "Mechanoluminescence: An assay for lymphocyte analysis in neoplasia". Journal of Bioluminescence and Chemiluminescence. 7 (4): 239–244. doi:10.1002/bio.1170070403. PMID   1442175.
  22. ↑ Hurt, C. R.; Mcavoy, N.; Bjorklund, S.; Filipescu, N. (October 1966). "High Intensity Triboluminescence in Europium Tetrakis (Dibenzoylmethide)-triethylammonium". Nature. 212 (5058): 179–180. Bibcode:1966Natur.212R.179H. doi:10.1038/212179b0. S2CID   4165699.
  23. ↑ Fontenot, Ross; Bhat, Kamala; Hollerman, William A; Aggarwal, Mohan (1 September 2016). "Europium Tetrakis Dibenzoylmethide Triethylammonium: Synthesis, Additives, and Applications Review". ECS Meeting Abstracts. MA2016-02 (42): 3158. doi:10.1149/ma2016-02/42/3158.
  24. ↑ "Make Blue Smash-Glow Crystals (Triboluminescence Demonstration)". YouTube .
  25. ↑ Marchetti, Fabio; Di Nicola, Corrado; Pettinari, Riccardo; Timokhin, Ivan; Pettinari, Claudio (10 April 2012). "Synthesis of a Photoluminescent and Triboluminescent Copper(I) Compound: An Experiment for an Advanced Inorganic Chemistry Laboratory". Journal of Chemical Education. 89 (5): 652–655. Bibcode:2012JChEd..89..652M. doi:10.1021/ed2001494.
  26. ↑ Erikson J (Oct 1972). "N-acetylanthranilic acid. A highly triboluminescent material". J Chem Educ. 49 (10): 688. Bibcode:1972JChEd..49..688E. doi:10.1021/ed049p688.
  27. ↑ IUPAC , Compendium of Chemical Terminology , 2nd ed. (the "Gold Book") (1997). Online corrected version: (2006–) " triboluminescence ". doi : 10.1351/goldbook.T06499
  28. ↑ Note: This phenomenon can be demonstrated by removing ice from a freezer in a darkened room where ice makes cracking sounds from sudden thermal expansion. If the ambient light is dim enough, flashes of white light from the cracking ice can be observed.
  29. ↑ Chauhan, V.S.1 (2008), "Effects of strain rate and elevated temperature on electromagnetic radiation emission during plastic deformation and crack propagation in ASTM B 265 grade 2 titanium sheets", Journal of Materials Science, 43 (16): 5634–5643, Bibcode:2008JMatS..43.5634C, doi:10.1007/s10853-008-2590-5, S2CID   137105959 {{citation}}: CS1 maint: numeric names: authors list (link)
  30. ↑ Srilakshmi, B.; Misra, A. (8 September 2005). "Secondary electromagnetic radiation during plastic deformation and crack propagation in uncoated and tin coated plain-carbon steel". Journal of Materials Science. Springer Science and Business Media LLC. 40 (23): 6079–6086. doi:10.1007/s10853-005-1293-4. ISSN   0022-2461. S2CID   135922668.
  31. ↑ Chauhan, Vishal S.; Misra, Ashok (1 July 2010). "Electromagnetic radiation during plastic deformation under unrestricted quasi-static compression in metals and alloys". International Journal of Materials Research. Walter de Gruyter GmbH. 101 (7): 857–864. doi:10.3139/146.110355. ISSN   2195-8556. S2CID   138866328.
  32. ↑ KUMAR, Rajeev (2006), "Effect of processing parameters on the electromagnetic radiation emission during plastic deformation and crack propagation in copper-zinc alloys", Journal of Zhejiang University Science A, 7 (1): 1800–1809, doi:10.1631/jzus.2006.a1800, S2CID   122149160
  33. ↑ Frid, V; Rabinovitch, A; Bahat, D (7 July 2003). "Fracture induced electromagnetic radiation". Journal of Physics D: Applied Physics. 36 (13): 1620–1628. Bibcode:2003JPhD...36.1620F. doi:10.1088/0022-3727/36/13/330. S2CID   250758753.
  34. ↑ Frid, V. (2000), "Electromagnetic radiation method water-infusion control in rockburst-prone strata", Journal of Applied Geophysics, 43 (1): 5–13, Bibcode:2000JAG....43....5F, doi:10.1016/S0926-9851(99)00029-4

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