Cadmium

Cadmium is a soft, ductile, bluish-white metallic element with the symbol Cd and atomic number 48. It has an atomic weight of 112.414 u and a density of 8.65 g/cm3. Cadmium has a relatively low melting point of 321.07°C and boiling point of 767°C. It mainly exists in the +2 oxidation state. Cadmium rarely occurs as a pure element, instead found in ores like greenockite (CdS) and extracted as a by-product during zinc, lead, and copper production.

Cadmium has some niche uses in electronics. It is used in some semiconductors including cadmium sulfide (CdS) which can detect radiation levels. Cadmium selenide (CdSe) also has uses in LEDs, photoresistors, and solar cells. Cadmium telluride (CdTe) is applied in photovoltaic solar panels as a semiconductor material. Some nickel-cadmium (NiCd) batteries also contain cadmium.

However, due to its toxicity, many cadmium applications are being phased out and replaced. Cadmium compounds are still utilized as pigments and coatings in electronics. But overall, cadmium’s importance in electronics is diminishing compared to its heyday several decades ago, though it retains some specialized high-tech uses.