Surf Wiki
Save to docs
general/infrared-sensor-materials

From Surf Wiki (app.surf) — the open knowledge base

Triglycine sulfate

Triglycine sulfate

Triglycine sulfate (TGS) is a chemical compound with a formula (NH2CH2COOH)3·H2SO4. The empirical formula of TGS does not represent the molecular structure, which contains protonated glycine moieties and sulfate ions. TGS with protons replaced by deuterium is called deuterated TGS or DTGS; alternatively, DTGS may refer to doped TGS. By doping the DTGS with the amino acid L-Alanine, the crystal properties are improved and the new material is called Deuterated L-Alanine doped Triglycine Sulfate (DLATGS or DLTGS). These crystals are pyroelectric and ferroelectric which allows their use as photodetector elements in infrared spectroscopy and night vision applications. TGS detectors have also been used as the target in vidicon cathode ray imager tubes.

TGS has a critical point for the order parameter of polarization, at 322.5 K.

Crystal structure and properties

Crystal structure of TGS. Hydrogen atoms are not

shown.]]

TGS crystals may be formed by evaporation of an aqueous solution of sulfuric acid and a greater than three-fold excess of glycine. They belong to the polar space group P21 and therefore are pyroelectric and ferroelectric at room temperature, exhibiting spontaneous polarization along the b-axis ([010] direction). The Curie temperature of the ferroelectric transition is 49 °C for TGS and 62 °C for DTGS. The crystal structure consists of SO42−, 2(N+H3CH2COOH) (G1 and G2 in the crystal-structure diagram), and +NH3CH2COO− (G3) species held together by hydrogen bonds. These bonds are easily broken by the polar molecules of water, which leads to the hygroscopicity of TGS – its crystals are easily etched by water. Along the b-axis, the G1-SO4 and G2-G3 layers are stacked alternately. The nearest two neighboring layers with identical chemical composition are rotated 180° around the b-axis against each other. DTGS and DLATGS materials are derivatives of TGS which have better pyroelectric properties and give less detector noise as can be shown in the following table.

AC Resistivity at 1 kHz (Ω.cm×1010)1.752.4

Typical performance of DLATGS detectors

The typical performance and pyroelectric properties of DLATGS detectors of 1.3 and 2.0 mm in diameter of the element size are shown in the table below.

2.0Typical3.20E-5302.00E-8 Maximum3.50E+825 (at 25 μm)0.0034.50E-10

References

References

  1. Kwan-Chi Kao. (2004). "Dielectric phenomena in solids: with emphasis on physical concepts of electronic processes". Academic Press.
  2. "Pyroelectric Detectors: Materials, Applications, and Working Principle".
  3. Gonzalo, J. A.. (1966-04-15). "Critical Behavior of Ferroelectric Triglycine Sulfate". Physical Review.
  4. Subramanian Balakumar and Hua C. Zeng. (2000). "Water-assisted reconstruction on ferroelectric domain ends of triglycine sulfate (NH2CH2COOH)3·H2SO4 crystals". J. Mater. Chem..
  5. Pandya, G. R.. (1980). "Crystallization of glycine-sulfate". Journal of Crystal Growth.
  6. Wood, E.A.. (1957). "Monoclinic glycine sulfate: crystallographic data". Acta Crystallogr..
  7. Aggarwal, M.D.. (2010). "Pyroelectric materials for uncooled infrared detectors : processing, properties, and applications". National Aeronautics and Space Administration, Marshall Space Flight Center.
  8. (1972-02-29). "Development of improved Pyroelectric Detectors".
  9. "Pyroelectric materials".
  10. (1997-10-15). "Growth and stability of pure and amino doped TGS crystals". Materials Chemistry and Physics.
  11. "Pyroelectric materials for uncooled infrared detectors: processing, properties, and applications.". NASA Technical Memorandum.
  12. Srinivasan, M. R.. (1984-05-01). "Pyroelectric materials". Bulletin of Materials Science.
  13. Company, Leonardo. "DLATGS Detectors".
  14. Components, Laser. "D31 / LT31 Series Single Channel Voltage Mode Pyroelectric Detectors".
Info: Wikipedia Source

This article was imported from Wikipedia and is available under the Creative Commons Attribution-ShareAlike 4.0 License. Content has been adapted to SurfDoc format. Original contributors can be found on the article history page.

infrared-sensor-materials sulfates
Want to explore this topic further?

Ask Mako anything about Triglycine sulfate — get instant answers, deeper analysis, and related topics.

Research with Mako

Free with your Surf account

Content sourced from Wikipedia, available under CC BY-SA 4.0.

This content may have been generated or modified by AI. CloudSurf Software LLC is not responsible for the accuracy, completeness, or reliability of AI-generated content. Always verify important information from primary sources.

Report