Kinetic Solute Trapping Models for Silicon Anode Active Material Atomization
Kinetic solute trapping in rapid atomization suppresses coarse silicon crystallites by overriding equilibrium partitioning above critical interface speeds.
Scherrer Broadening
Meaning
X-ray diffraction peak expansion caused by sub-micron crystallite domain boundaries allows mathematical calculation of mean crystallite size in polycrystalline materials. Within materials characterization and powder diffraction analysis, scherrer broadening measures the physical widening of diffraction peaks to estimate coherent domain sizes below two hundred nanometers. The technique applies to nano-crystalline powders and active battery materials, losing accuracy when crystallite dimensions exceed sub-micron scales.
Peak Broadening
Incomplete destructive interference occurs when X-rays scatter from finite numbers of parallel lattice planes within small crystallite domains. Peak width increases inversely with decreasing domain size as domain boundaries truncate crystal lattice periodicity. Instrumental broadening and lattice strain effects also contribute to total peak width, requiring mathematical deconvolutions using standard calibration samples.
Size Calculation
Applying the Scherrer equation links full width at half maximum values directly to volume-weighted average crystallite dimensions. X-ray wavelength, diffraction angle, and dimensionless shape factors enter the formula to determine primary crystallite domain scale. Battery materials researchers track crystallite size changes during thermal processing to optimize nano-grain structures for maximum lithiation stability.
Analytical Limit
Peak broadening analysis becomes unreliable when microstrain, compositional gradients, or stacking faults dominate diffraction line profiles. Lattice strain caused by mechanical milling or phase transformations convolutes pure size broadening signals, introducing significant calculation error. Complementary characterization using transmission electron microscopy validates crystallite size estimates in highly deformed or heterogeneous active materials.
Disentangling strain effects from domain size effects requires multi-peak Williamson-Hall analysis across several diffraction reflections.