Bulksurface

Bulksurface is a concept used in materials science and solid-state physics to describe the coupled behavior of a material's bulk interior and its surface. The term emphasizes that properties are not determined solely by the interior but are significantly influenced by the surface, where atomic coordination is reduced and chemical interactions with the environment differ. In nanoscale systems, bulksurface effects dominate because the surface atoms account for a larger fraction of total atoms. Surface energy, reconstruction, adsorption, and catalytic activity are central bulksurface phenomena. The exchange of mass, charge, and energy between bulk and surface can alter diffusion, phase stability, and mechanical properties, leading to size-dependent melting points, strength, and corrosion behavior.

Measurement and modelling: Investigations use surface-sensitive techniques such as X-ray photoelectron spectroscopy (XPS), low-energy electron diffraction (LEED), scanning tunneling microscopy (STM), and depth profiling. Computational approaches combine density functional theory for surface states with continuum or phase-field models to capture bulksurface coupling.

Applications include heterogeneous catalysis, where active sites are on the surface while the bulk supports influence activity and stability; nanomaterials, where bulksurface interactions govern properties; and electronic devices, where surface states affect conduction and junction behavior.

See also: bulk, surface science, surface energy, catalysis, thin film, interface.