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|Section2= |Section3= |Section7= |Section8= }} Lead selenide (PbSe), or lead(II) selenide, a selenide of lead, is a semiconductor material. It forms cubic crystals of the NaCl structure; it has a direct bandgap of 0.27 eV at room temperature. (Note that incorrectly identifies PbSe and other IV–VI semiconductors as indirect gap materials.) It is a grey crystalline solid material. It is used for manufacture of infrared detectors for thermal imaging, operating at wavelengths between 1.5–5.2 µm. It does not require cooling, but performs better at lower temperatures. The peak sensitivity depends on temperature and varies between 3.7–4.7 µm. Single crystal nanorods and polycrystalline nanotubes of lead selenide have been synthesized via controlled organism membranes. The diameter of the nanorods were approx. 45 nm and their length was up to 1100 nm, for nanotubes the diameter was 50 nm and the length up to 2000 nm. Lead selenide nanocrystals embedded into various materials can be used as quantum dots, for example in nanocrystal solar cells. Lead selenide is a thermoelectric material. The material was identified as a potential high temperature thermoelectric with sodium or chlorine doping by Alekseva and co-workers at the A.F. Ioffe Institute in Russia. Subsequent theoretical work at Oak Ridge National Laboratory, USA predicted that its p-type performance could equal or exceed that of the sister compound, lead telluride. Several groups have since reported thermoelectric figures of merit exceeding unity, which is the characteristic of a high performance thermoelectric. The mineral clausthalite is a naturally occurring lead selenide. It may be formed by direct reaction between its constituent elements (lead and selenium). == Infrared detection == PbSe is one of the first materials sensitive to the infrared radiation used for military applications. Early research works on the material as infrared detector were carried out during the 1930s and the first useful devices were processed by Germans, Americans and British during and just after World War II. Since then, PbSe has been commonly used as an infrared photodetector in multiple applications, from spectrometers for gas and flame detection to infrared fuzes for artillery ammunition or Passive Infrared Cueing systems (PICs). As a sensitive material to the infrared radiation, PbSe has unique and outstanding characteristics: it can detect IR radiation of wavelengths from 1.5 to 5.2 µm (mid-wave infrared window, abbreviated MWIR - in some special conditions it is possible to extend its response beyond 6 µm), it has a high detectivity at room temperature (uncooled performance), and due to its quantum nature, it also presents a very fast response, which makes this material an excellent candidate as detector of low cost high speed infrared imagers. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Lead selenide」の詳細全文を読む スポンサード リンク
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