Title: INDIUM

ENDANGERED ELEMENTS

‘Indium is one of the most critical elements because of the way that we use it,’ says Mike Pitts, from the UK’s Chemistry Innovation Knowledge Transfer Network. For example, every liquid crystal display screen contains indium components. About 45 per cent of all indium extracted is used for the indium tin oxide that lines solar cells and flat panel displays. The Earth’s crust contains roughly three times as much indium as silver, although silver can be mined far more efficiently. In 2007 the US Geological Survey estimated that we will run out of indium for extraction in less than two decades, although the indium industry tends to dispute such figures.

Chemistry World | January 2011 | 52

Chemistry news, research and opinions | Chemistry World

USES AND TOXICITY

A relatively scarce element in the Earth's crust, indium has a few possible uses in LCD screens and other devices. Indium tin oxide is often used as a coating for screens, and can be used to make transparent electrodes inside the glass layers of an LCD screen.

LCD manufacturing largely drives demand for indium, though it's also used in photovoltaic cells. The metal's compounds can be toxic, and people who have inhaled its indium tin oxide form in an occupational setting can contract a rare disease called indium lung.

Four Materials Illustrate Hazards Of Electronics Manufacturing | WisContext

LONG TERM SCARCITY

The demand for indium could intensify significantly if thin-film materials relying on this element—specifically, copper-indium-gallium-selenide (CIGS) and III-V thin-films—become preferred photovoltaic (PV) materials. Yet the indium supply is potentially fragile for several reasons:

• Markets for metallic forms of indium are small, (about 1000 tonnes per annum [tpa] of world production and use. Any new, widespread use could dramatically alter overall demand, which could grow faster than production capacity for up to about a decade, given the length of time needed to significantly increase production capacity. During this decade, indium prices could be high and volatile enough that thin-film manufacturers find it uncompetitive compared to competing PV materials.

• Indium is currently produced almost solely as a byproduct of zinc smelting and refining.1 As a byproduct, indium benefits from sharing some production costs with its associated main product. Thus, costs of producing indium as a byproduct are undoubtedly lower than if it were produced by itself. If future demand for indium exceeds the quantities available as a byproduct, more costly sources of indium will be necessary to satisfy demand from thin-film producers, raising the possibility that indium prices could be much higher than current and recent prices.

• Relevant for the long term, indium is one of the scarcer elements, at least in terms of average abundance in the Earth’s crust. Thus, even if indium were available in the short to medium term at prices making CIGS materials competitive with competing photovoltaic materials, such competitiveness could be short lived.

The Availability of Indium: The Present, Medium Term, and Long Term (nrel.gov)

RECYCLING

Besides is primary production, indium is also produced from secondary production. World secondary refined indium production resulted almost exclusively from the recycling of manufacturing waste rather than recovery from end-of-life (EOL). Only around 1 % of indium is recycled from these products because of indium is usual used only in minor concentrations. Overall, the secondary supply has been a significant contributor to the total supply.

Indium can be considered a critical material for display technology because there are few substitutes.

02/11/2020  https://www.esmfoundation.org/material-of-the-month-indium/