Does antimony has more metallic property than indium?

Tellurium properties

Tellurium is a quasi-metallic element with the symbol Te, belonging to group ⅵ A in the periodic table of elements, with an atomic number of 52 and an atomic mass of 127.6. Tellurium has two allotrophes. One belongs to the hexagonal system, with atoms arranged in a spiral shape and a silver-white metallic luster. The other is an amorphous, black powder. 

Tellurium has a melting point of 452℃ and a boiling point of 1390℃. It is brittle and has chemical properties similar to antimony. Its electronic configuration is (Kr) 4D105S25P4, and its oxidation states are -2, +1, +2, +4, +6. At room temperature, tellurium can be oxidized and interact with halogens to form halides such as TeF6 and TeCl4. Tellurium soluble in sulfuric acid, nitric acid, aqua regia, potassium cyanide, potassium hydroxide; Insoluble in water, carbon disulfide. 

Tellurium burns in air with a blue flame, forming tellurium dioxide. When very low concentrations of tellurium are inhaled, the human body produces a potent garlic odor on the exhale, in sweat and urine. Tellurium is one of seven sparse metals that are generally associated minerals, and independent deposits are rare, as is tellurium.

Tellurium preparation method

Tellurium is made in a similar way to selenium, which is often extracted with selenide and then separated into telluride. Then, the telluride is calcinated with concentrated sulfuric acid to be converted into TeO2 telluride or H2TeO3 tellurite, and then reduced with sulfur dioxide or carbon:

H2TeO3+2SO2+H2O─→Te+2H2SO4 or the element tellurium is obtained by electrolysis. The purification methods of tellurium include electrolytic refining, vacuum distillation and extraction.

Tellurium applications

About 80% of tellurium consumption is in the metallurgical industry: adding small amounts of tellurium to steel and copper alloys improves their machining properties and increases their hardness; Tellurium is used as a carbide stabilizer in white cast iron to make the surface strong and wear resistant. Lead containing small amounts of tellurium, which can improve the corrosion resistance, wear resistance and strength of materials, used as sheath for submarine cables. Tellurium was added to harden lead, which was used to make battery plates and print type. 

Tellurium can be used as an additive in petroleum cracking catalysts and as a catalyst for making ethylene glycol. Tellurium oxide is used as a colorant in glass. High purity tellurium can be used as alloy component of thermoelectric materials. Bismuth telluride is a good cooling material. Tellurium and some tellurides are semiconductor materials. Ultrapure tellurium single crystal is a new type of infrared material.

In addition, tellurium is used as a time-delayed fuse in timed explosives. Tellurium, a raw material for bactericides, is used in medicine to extract iodine isotopes and cure thyroid diseases.

Mainly used for petroleum cracking catalyst, electrobath brightener, glass coloring material, added to steel to increase its DUCtility, added to lead to increase its strength and corrosion resistance. Tellurium and its compounds are also semiconducting materials.

The properties of indium metal

Indium, a metallic element with the symbol In and atomic number 49, is located In group IIIA of the fifth period of the periodic table. Indium is a silver-gray, very soft, fusible metal. The melting temperature of 156.61 ℃. The boiling point of 2060 ℃. The density of 7.30 g/cm3. Liquid indium can soak into glass and stick to surfaces it touches leaving black marks.

Indium is weakly radioactive, and natural indium has two main isotopes, of which in-113 is a stable nuclide and In-115 is β-decayed. Therefore, avoid direct contact as much as possible in use.

High purity indium characteristics

I: indium metal is silvery white and slightly bluish, shiny and makes a sound when it bends. Its alloy with copper, silver and gold is used to make dentures. Melting point 156.61°C, boiling point 2080°C, density 7.3 g/cm & SUP3; ; It's malleable. It's softer than lead.

Indium has a low melting point (156.61°C), a high boiling point (2080°C), good conductivity, good ductility, softer than lead, and can be scratched by fingernails; Strong plasticity, can be pressed into extremely thin sheet metal. Its oxide can form transparent conductive film and other characteristics, in recent years, indium tin oxide (ITO), semiconductor, low melting point alloy and other applications. 

In particular, indium tin oxide (ITO) has been widely used as a transparent conductive film due to its visible light transmittance of more than 95%, UV absorption rate of more than 70%, microwave attenuation rate of more than 85%, good conductivity and processing performance, and abrasion and chemical corrosion resistance. With the rapid development of IT industry, used in notebook computers, televisions and mobile phones and other new type of liquid crystal display (LCD) and touch screen, architectural glass, etc., as a transparent electrode coating of ITO target materials (about 70% of indium dosage) with a sharp increase in the level of, make the indium demand is to average annual growth rate of more than 30% of the increase. 

The rapid growth of the flat panel display on the world market of indium in the world in the production of the main end users, including flat-screen televisions, desktop computer monitor, internet-enabled laptops, mobile phones and other main rapid development and application of the flat panel display, makes the international market demand for indium surging, and there is no new is used to replace ITO materials research.

III: From room temperature to melting point, indium interacts slowly with oxygen in the air, forming a very thin oxide film on the surface. At higher temperatures, indium interacts with oxygen, halogen, sulfur, selenium, tellurium and phosphorus. Indium oxidizes slowly in air; Bulk metal indium does not react with boiling water or alkali, but powdered indium can react with water to form indium hydroxide. 

Indium interacts slowly with cold dilute acid and is easily soluble in concentrated hot inorganic acid, acetic acid and oxalic acid. Indium can be used as a coating or alloy with other metals to enhance the corrosion resistance of engine bearings; Indium has excellent reflectance and can be used to manufacture mirrors. Silver-lead-indium alloy can be used as bearing material for high speed aero-engine. The melting point of fusible wood alloy can be reduced by 1.45℃ for every 1% indium added. Indium compound semiconductors include indium antimonide (communication laser light source, solar cell), indium phosphide and indium antimonide (infrared detection, optical magnetic devices, solar energy converters, etc.).

IV: indium alloy can be used as reactor control rod, which can detect neutron radiation sensitively; Can be used for landing module, landing, no embrittlement, no cracking.

The Application of the indium

Due to its strong light permeability and electrical conductivity, indium is mainly used in the production of ITO targets (used in the production of liquid crystal displays and flat screens). This use is the main consumption area of indium ingots, accounting for 70% of global indium consumption.

The next largest consumer segments are electronics and semiconductors, which account for 12 percent of global consumption; Solder and alloy, 12%; Research accounted for 6%. In addition, because of its softer nature, it is also used in some industries that require metal filling. Such as: vacuum gap filling material at higher temperature.

In medicine, liver, spleen, bone marrow scanning with indium colloid. Indium-dtpa for brain and kidney scans. Indium-fe (OH)3 particles were used for lung scanning. The placenta was scanned with indium-Fe-ascorbic acid. Liver blood pool scan delivers ferritin with indium.

Gallium and indium alloys are combined into liquid metals to form a solid-solution gold that can be liquid at room temperature and has a surface tension of 500 millinewtons per meter. This means that, when placed on a flat table, the alloy will remain an almost perfect sphere without any external force. When stimulated with a small amount of current, the sphere's surface tension decreases and the metal stretches across the table. If the charge changes from negative to positive, the liquid metal becomes spherical again. Changing the voltage can also adjust the surface tension of the metal and the viscosity of the metal block, so that it changes into a different structure. The research could also be used to help repair severed nerves in humans to avoid long-term disability. Researchers say the breakthrough could help build better circuits and self-healing structures.