Adsorption is a phenomenon in which molecules or atoms from a substance adhere to the surface of another substance. It is a process where a material (adsorbent) attracts and holds particles or molecules (adsorbate) onto its surface. This attraction occurs due to intermolecular forces, such as van der Waals forces, electrostatic forces, or chemical bonding.
When adsorption takes place, the adsorbate forms a thin layer on the surface of the adsorbent, resulting in an increase of concentration or accumulation of the adsorbate at the interface. It differs from absorption, which involves the penetration of a substance within the bulk of another substance.
Adsorption is commonly observed in various fields, such as chemistry, physics, environmental science, and industrial processes. It plays a crucial role in many applications, including purification, separation, catalysis, gas storage, and control of pollutants. It can also significantly affect the behavior of substances in biological systems, such as the adsorption of drugs onto cell membranes.
The extent and rate of adsorption are influenced by factors such as temperature, pressure, surface area, surface chemistry, and the properties of the adsorbate and adsorbent. Adsorption is often characterized using techniques like adsorption isotherms, which describe the amount of adsorbate at equilibrium as a function of pressure or concentration.
Overall, adsorption is a fundamental process that underlies various scientific and practical phenomena, and its understanding and optimization have important implications in numerous industries and fields of research.
