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Zinc sulfide (or zinc sulphide) is an inorganic compound with the chemical formula of ZnS. This is the main form of zinc found in nature, where it mainly occurs as the mineral sphalerite . Although this mineral is usually black because of various impurities, the pure material is white, and it is widely used as a pigment.
[18] [19] This led to the discovery by Yasumitsu Aoki (Nemoto & Co.) of materials with luminance approximately 10 times greater than zinc sulfide and phosphorescence approximately 10 times longer. [20] [21] This has relegated most zinc sulfide based products to the novelty category. Strontium aluminate based pigments are now used in exit signs ...
Silver, added to zinc sulfide to produce a phosphor/scintillator used in radium dials, spinthariscopes, and as a common blue phosphor in color CRTs, and to zinc sulfide-cadmium sulfide used as a phosphor in black-and-white CRTs (where the ZnS/(Zn,Cd)S ratio determines the blue/yellow balance of the resulting white); short afterglow
The best known type is a copper-activated zinc sulfide (ZnS) and the silver-activated zinc sulfide (zinc sulfide silver). The host materials are typically oxides, nitrides and oxynitrides, [2] sulfides, selenides, halides or silicates of zinc, cadmium, manganese, aluminium, silicon, or various rare-earth metals. The activators prolong the ...
Strontium aluminates are now the longest lasting and brightest phosphorescent material commercially available. For many phosphorescence-based purposes, strontium aluminate is a superior phosphor to its predecessor, copper-activated zinc sulfide, being about 10 times brighter and 10 times longer glowing.
Various preparations of the phosphor compound can be used to produce different colors of light. For example, doping zinc sulfide phosphor with different metals can change the emission wavelength. [4] Some of the colors that have been manufactured in addition to the common phosphors are green, red, blue, yellow, purple, orange, and white.
When a molecule absorbs a photon, the photon energy is converted and increases the molecule's internal energy level. Likewise, when an excited molecule releases energy, it can do so in the form of a photon. Depending on the energy of the photon, this could correspond to a change in vibrational, electronic, or rotational energy levels. The ...
The standard Gibbs free energy of formation (G f °) of a compound is the change of Gibbs free energy that accompanies the formation of 1 mole of a substance in its standard state from its constituent elements in their standard states (the most stable form of the element at 1 bar of pressure and the specified temperature, usually 298.15 K or 25 °C).