Defectinduced

Defectinduced is a term used to describe phenomena in which defects in a material or device drive changes in properties or behavior. It spans fields such as solid-state physics, materials science, and catalysis. Defects can be intrinsic, like vacancies, interstitials, and antisites, or extrinsic, such as dopants or impurities. The distribution and nature of defects determine their impact on electronic, optical, mechanical, and chemical properties.

Defect types include point defects (vacancies, interstitials, substitutions), line defects (dislocations), and planar defects (grain boundaries, stacking faults). Defects may cluster or form complexes, creating defect-rich regions or interfaces with distinct properties.

Mechanisms by which defects induce changes include localized electronic states within a band gap that can trap or donate carriers; scattering and trapping that affect transport; and strain fields that alter diffusion, strength, and phase stability. Defects can also serve as active sites in catalysis or nucleation centers for phase changes.

Examples include semiconductors, where defects modify conductivity and luminescence; metals, where defects can strengthen materials or affect creep; oxides, where oxygen vacancies influence ionic conduction and catalytic activity; and nanomaterials, where defects can govern magnetism and optical behavior.

Study and control: defect engineering aims to tailor properties by controlling defect type and concentration through processing, irradiation, annealing, or alloying. Characterization uses microscopy (TEM, STM), spectroscopy, diffraction, and computational modeling (DFT, MD).