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Fine ZnS powder is an efficient photocatalyst, which produces hydrogen gas from water upon illumination. Sulfur vacancies can be introduced in ZnS during its synthesis; this gradually turns the white-yellowish ZnS into a brown powder, and boosts the photocatalytic activity through enhanced light absorption.
[10] [18] In pure form, it is a semiconductor, but transitions to a conductor as the iron content increases. [19] It has a hardness of 3.5 to 4 on the Mohs scale of mineral hardness. [20] It can be distinguished from similar minerals by its perfect cleavage, its distinctive resinous luster, and the reddish-brown streak of the darker varieties. [21]
A compound semiconductor is a semiconductor compound composed of chemical elements of at least two different species. These semiconductors form for example in periodic table groups 13–15 (old groups III–V), for example of elements from the Boron group (old group III, boron, aluminium, gallium, indium) and from group 15 (old group V, nitrogen, phosphorus, arsenic, antimony, bismuth).
Zinc sulfate is an inorganic compound with the formula ZnSO 4.It forms hydrates ZnSO 4 ·nH 2 O, where n can range from 0 to 7. All are colorless solids. The most common form includes water of crystallization as the heptahydrate, [4] with the formula Zn SO 4 ·7H 2 O.
BaS + ZnSO 4 → ZnS · BaSO 4. This route affords a product that is 29.4 wt % ZnS and 70.6 wt % BaSO 4. Variations exist, for example, more ZnS-rich materials are produced when zinc chloride is added to the mixture of zinc sulfate and barium sulfide. [1] Barium sulfide is produced by carbothermic reduction of barium sulfate.
There are three reasons to briquette the calcine: to ensure free downward movement of the charge; to permit heat transfer across a practical size cross-section; to allow adequate porosity for the passage of reduced zinc vapour to the top of the retort. The reduced zinc vapour that is collected at the top of the retort is then condensed to a liquid.
Zinc oxide is an inorganic compound with the formula Zn O.It is a white powder which is insoluble in water. ZnO is used as an additive in numerous materials and products including cosmetics, food supplements, rubbers, plastics, ceramics, glass, cement, lubricants, [12] paints, sunscreens, ointments, adhesives, sealants, pigments, foods, batteries, ferrites, fire retardants, semi conductors ...
Zinc selenide is the inorganic compound with the formula ZnSe. It is a lemon-yellow solid although most samples have a duller color due to the effects of oxidation. It is an intrinsic semiconductor with a band gap of about 2.70 eV at 25 °C (77 °F), equivalent to a wavelength of 459 nm.