FeFeCN

FeFeCN, also known as ferric ferrocyanide or Prussian blue, is a pigment with the chemical formula Fe7(CN)18. It is a dark blue compound that has been used as a dye and pigment for centuries. The compound is formed by the reaction of ferric salts with ferrocyanide ions. Its structure is a complex coordination polymer, with iron atoms in two different oxidation states. Prussian blue is insoluble in water, which contributes to its stability as a pigment. Historically, it was a popular and cost-effective blue pigment used in paints, inks, and textiles. Beyond its artistic applications, Prussian blue has found use in various industrial and scientific fields. It can be used as an antidote for thallium and cesium poisoning due to its ability to bind these radioactive isotopes. It also has applications in electrochemistry and as a component in some types of solar cells. The synthesis of Prussian blue can be achieved through several methods, typically involving the precipitation of iron salts with ferrocyanides. The exact shade and properties of the pigment can vary slightly depending on the specific preparation method.