Germanium

Germanium is a chemical element with the symbol Ge and atomic number 32. It looks grayish-white and is hard but brittle, similar to silicon. Germanium is a special kind of element called a metalloid, which means it has properties of both metals and nonmetals.

Germanium was predicted in 1869 by Dmitri Mendeleev when he created his famous periodic table. It was finally discovered in 1886 by Clemens Winkler in a mineral called argyrodite. Winkler named it after his home country, Germany.

Today, germanium is important for making electronics. It is used in transistors and many modern devices like fibre-optic systems, infrared optics, solar cell applications, and light-emitting diodes (LEDs). It is also used in chemical reactions and in making very tiny wires called nanowires.

History

In 1869, the scientist Dmitri Mendeleev predicted that some elements had not yet been discovered. He said one would fit between silicon and tin, and he called it ekasilicon. He thought it would weigh about 70.

In 1885, a new mineral was found near Freiberg, Saxony. A chemist named Clemens Winkler studied it and found a new element in 1886. He named it germanium after Germany, his home country. This new element matched what Mendeleev had predicted.

Winkler made new compounds with germanium and shared his findings in 1887. Germanium was later found to be useful in electronics, especially after 1945. It was used in early radar devices and in the first transistor in 1948. Even though silicon later became more common, germanium is still used in some special tools today.

Characteristics

Germanium is a brittle, silvery-white material that acts like a semiconductor. It has a shiny, metallic look and forms a special type called α-germanium, which shares the same crystal shape as silicon and diamond. Under very high pressure, germanium changes into another form called β-germanium, similar to a metal called tin.

Germanium is useful because it can control electricity, making it important for tiny electronic parts. It can also stretch into long, thin lines that sometimes cause problems in older electronic devices by creating unwanted paths for electricity to flow.

Chemistry

Germanium slowly changes when exposed to air, forming a compound called GeO₂. It does not dissolve in weak acids or alkalis but can dissolve in strong acids and reacts strongly with hot molten alkalis to make germanates.

Germanium mostly exists in a form called +4, but it can also be found in +2 and other rare forms. It forms different compounds with oxygen, such as germanium dioxide (GeO₂) and germanium monoxide (GeO). These compounds have special properties, like being clear to certain types of light.

Germanium also makes compounds with other elements, such as sulfur and chlorine. For example, it forms germanium disulfide (GeS₂) and germanium tetrachloride (GeCl₄). These compounds can be used to make other germanium-based materials.

Organogermanium compounds, which include germanium combined with carbon, were first made in 1887. These compounds can be used in different ways, including in electronics. Some organogermanium compounds were once thought to have special health benefits, but this is not well proven.

Using special chemicals, germanium can form bonds with oxygen, creating compounds known as germanones.

Isotopes

Main article: Isotopes of germanium

Germanium occurs naturally in five different forms, called isotopes. The most common is ⁷⁴Ge, making up about 36.52% of all germanium. Another isotope, ⁷⁶Ge, is very slightly radioactive and changes over an extremely long time.

Besides these natural isotopes, scientists have made over 27 other radioactive isotopes of germanium in labs. The most stable of these is ⁶⁸Ge, which changes over about 271 days.

Occurrence

See also: Category:Germanium minerals

Germanium is created in stars through a process called the s-process. It can be found in some of the farthest stars and in the atmosphere of Jupiter.

On Earth, germanium is quite rare, found in very small amounts in the crust. It is mainly found in a few minerals such as argyrodite, briartite, germanite, renierite, and sphalerite. These minerals are rarely found in amounts large enough to mine. However, some coal deposits, especially near Xilinhaote in Inner Mongolia, contain surprisingly high amounts of germanium.

Production

In 2011, about 118 tonnes of germanium were made around the world. Most of it came from China, with smaller amounts from Russia and the United States. Germanium is often found as a by-product when mining zinc, especially in certain types of deposits. It can also be found in silver, lead, and copper ores, as well as in the ash from coal-powered plants.

The process to get germanium from its ores involves heating the materials to turn them into oxides. These oxides are then treated with acids and other chemicals to separate out the germanium. The final product can be used to make glass and materials for electronics. Different methods are used depending on whether the germanium is needed for making steel or for more pure applications like semiconductors.

Applications

Germanium is used in many important ways. About a quarter goes into making fiber optic wires, and another chunk is used for seeing in infrared light. It also helps make plastics clearer and stronger, and is used in electronics and solar power.

Germanium is great for special kinds of glass that bend light well and don’t spread it out too much. This makes it perfect for cameras, microscopes, and the tiny wires that carry internet signals. It can also be made clear to see heat, which is useful for night-vision goggles and cameras that find hot spots.

In electronics, germanium mixes with silicon to make super-fast chips. It is also used in solar panels for space, like on robots that explore Mars. Some old music gear used germanium to make special sounds, and scientists are studying it for tiny sensors inside the body.

Germanium and health

Germanium is not known to be important for plants or animals to stay healthy. It is usually found only in very small amounts in rocks and other materials, and the amounts used in products are so small that they are not likely to be eaten. Because of this, germanium does not usually affect health or the environment in a harmful way.

Some people have sold germanium supplements as a way to treat serious illnesses, but there is no proof that they work. In fact, some research shows that these supplements can be harmful. Certain forms of germanium used in supplements have been linked to health problems in people who used them for a long time. Some germanium compounds can also hurt certain types of bacteria, but they can be dangerous to humans if not handled properly.

Precautions for chemically reactive germanium compounds

While germanium itself is safe to use, some man-made germanium compounds can be very harmful if you come into contact with them. For example, certain germanium liquids and gases can irritate the eyes, skin, lungs, and throat.