Structural Defects Detection

Nanoparticles, defined as particles with dimensions ranging from 1 to 100 nanometers, have garnered significant attention in various fields due to their unique properties and extensive applications. However, the properties, such as electronic, optical, and mechanical properties of nanoparticles, can be significantly influenced by various structural defects that may occur during their synthesis, processing, or use.

• Vacancies: These defects occur when atoms are missing from the crystalline lattice structure. Vacancies can disrupt the regular arrangement of atoms, leading to changes in electronic, optical, and mechanical properties, as well as thermal conductivity.
• Interstices: These defects occur when additional atoms occupy spaces (interstitial sites) between the primary atoms in the crystal lattice. Interstitial defects can introduce strain and alter the electronic states of the material.
• Dislocations: Dislocations are linear defects in the crystal structure where regular atomic arrangements are disrupted. Edge dislocations and screw dislocations can affect the mechanical properties of materials, influencing yield strength and ductility.
• Grain Boundaries: Grain boundaries occur where crystals of different orientations meet. The boundaries can affect the electrical conductivity, mechanical strength, and diffusion rates within the nanoparticles.
• Twin Boundaries: Twin boundaries occur when a portion of the crystal is a mirrored image of the adjoining portion and can influence the strength and hardness of materials.
• Stacking Faults: Stacking faults occur when there is an irregularity in the stacking sequence of atomic planes, potentially impacting material properties.
• Surface Defects: Due to their high surface-to-volume ratio, nanoparticles often have a high density of surface defects. These might include missing atoms, dangling bonds, or reconstruction at the surface, which can affect catalytic activity and chemical reactivity.
• Doping and Alloying: The intentional introduction of foreign atoms (dopants) into a nanoparticle's crystalline structure can create localized defects and modify properties such as conductivity, magnetism, and optical behavior.
• Irregular Shapes: Deviations from ideal geometric shapes (spheres, cubes, etc.) can introduce unique optical and electronic features.
• Porosity: Porous structures can enhance reactivity but may weaken structural integrity.

Therefore, detecting and quantifying these structural defects is crucial for optimizing their functionality in applications ranging from drug delivery and catalysis to energy storage and nanocomposite materials. Identifying structural defects is not just important for ensuring the quality of nanoparticles but also for enhancing their efficiency and reliability in real-world applications.

Nanoparticle Structural Defects Detection Techniques

STEMart focuses on the detection and characterization of structural defects in nanoparticles through advanced techniques.

High-Resolution Transmission Electron Microscopy (HRTEM)

HRTEM uses light and dark fringes to represent the interplanar spacing and enables researchers to observe the crystal structure and lattice defects in various nanomaterials at atomic resolution. It can be used to characterize structures such as point defects, stacking faults, dislocations, and precipitate grain boundaries.

Electron Backscatter Diffraction (EBSD)

EBSD places a fixed electron beam at a selected sampling point on the surface to offer crystallographic information, such as grain orientation, grain orientation distribution (micro-texture), and orientation relationship of the sample.

STEMart leverages state-of-the-art test methods that combine high-resolution imaging and advanced diffraction techniques, enhancing the quality and precision of defect detection. For more information about our nanoparticle structural defects detection service, please contact us.