Diffusion through colloidal shells under stress

Area of Science:

• Materials Science
• Physical Chemistry
• Colloid Science

Background:

• Solid permeability is traditionally linked to Eyring's activated diffusion mechanism.
• The influence of tensile stress on diffusion rates in solids lacks definitive experimental evidence.
• Understanding stress-induced changes in material transport is crucial for various applications.

Purpose of the Study:

• To experimentally investigate the effect of tensile stress on the diffusion rate of species through solids.
• To quantify the relationship between applied stress and the energy barrier for diffusion.

Main Methods:

• Utilized core-shell (liquid core-solid shell) colloidal particles as model systems.
• Employed osmotically sensitive colloidal particles to track encapsulated probe permeation.
• Applied controlled tensile stress to colloidal shells to measure diffusion changes.

Main Results:

• Demonstrated an unambiguous, linear reduction in the local energy barrier for diffusion under tensile stress.
• Quantified the direct impact of mechanical stress on the kinetics of species transport through solid materials.

Conclusions:

• Tensile stress significantly modifies the activated diffusion process in solids.
• The findings provide direct experimental validation of stress-dependent diffusion barriers.
• This work offers new insights into the mechanics of material transport under mechanical load.