Molecular Dynamics of NP–CNT Interfaces: Interfacial Interactions and Structural Evolution Across Size and Temperature

Abstract

CNT–metal nanoparticle interconnects are attractive for advanced and power electronic packaging, yet the atomistic mechanisms of nanoparticle–Carbon nanotube (NP–CNT) sidewall contact remain unclear under size and temperature variations. Here, molecular dynamics simulations establish a mechanism-consistent chain linking energetics, structural evolution, CNT mechanical accommodation, stress localization, and curvature-induced anisotropy in solid-state Ag NP–CNT contact. A direct Ag NP–NP benchmark highlights the fundamental difference: NP–CNT contact shows a much weaker energetic drive and lacks diffusion-driven neck growth. Therefore, interfacial adjustment is dominated by adsorption and coupled CNT indentation–bending–damping. Interfacial stresses concentrate near the contact boundary and penetrate into subsurface layers. Increasing temperature can reduces peak stress and broadens the stressed region. Systematic cases reveal that high temperature combined with small NP size activates late-time transient disordering followed by interface-adjacent recrystallization, producing a multi-grain, multiply twinned NP with Σ3{111}-related twins. At last the solid-state wetting analysis shows strong axial–circumferential anisotropy governed by indentation–bending coupling and cylindrical curvature. These results provide atomistic guidelines for choosing NP size, processing temperature, and CNT texture to balance adhesion, structural stability, and stress concentration.