Chemisorption and Physisorption of Water Vapors on the Surface of Lithium-Substituted Cobalt Ferrite Nanoparticles.

Abstract

Ferrimagnetic materials have the assembly of n-type porous semiconductors that shows the evidence of several physical properties used in electronic devices and technology. If the water vapors are brought closer to the surface of n-type semiconductors, then the electrons near the surface of materials are transferred from the conduction band to the electron-accepting level of the water molecule that provides chemisorbed layer of OH– ions. The conduction of electrons takes place only when H3O+ releases one proton to the nearest water molecule that accepts electrons while releasing another proton and so on. This mechanism is known as the Grotthuss chain reaction; it is the essential conduction mechanism of water and surface layers of water on the humidity-sensitive semiconducting materials. In this article, the humidity-sensing properties of Li-substituted cobalt ferrite nanoparticles prepared by the solution combustion method are reported. The result of the data suggested that the substitution of Li ions improved the formation of smaller grains of cobalt ferrite, which results in a rise within the surface area and improved the humidity sensitivity of ferrite nanoparticles.