Doped materials refer to materials that have been intentionally impregnated or infused with small amounts of foreign elements, known as dopants. These dopants are added to modify the electrical, optical, or magnetic properties of the material. Doped materials are commonly used in electronic devices, such as transistors and diodes, as well as in other applications such as sensors, solar cells, and catalysis. The doping process can either increase or decrease the conductivity of the material, depending on the type and concentration of dopants used. Research in this area focuses on understanding the doping mechanisms, optimizing doping techniques, and exploring new materials and dopants for various applications.