Nanoporous gold (NPG), characterized by a bicontinuous network of nanoscale solid ligaments and pore channels, exhibits exceptional physical and chemical properties. However, the limited strength and stiffness of traditional isotropic NPG (INPG) have constrained its engineering applications. To effectively enhance the mechanical properties of NPG, this work proposes an innovative anisotropic NPG (ANPG) architecture featuring unidirectional ligament orientation. By controlling spinodal decomposition parameters, ANPG models with preferentially aligned ligaments and INPG with random ligament orientation are constructed, spanning relative densities from 0.30 to 0.50. The ligament length and diameter of ANPG along the out-of-plane direction are twice those along other directions. Molecular dynamics simulations of tensile tests show that ANPG exhibits superior out-of-plane Young’s modulus and yield strength but reduced fracture strain compared to INPG. Crucially, ANPG maintains toughness comparable to INPG at relative densities below 0.4, offering an optimal strength-toughness balance for practical applications. Scaling law analysis demonstrates INPG follows classical bending-dominated Gibson-Ashby behavior, while ANPG exhibits a hybrid deformation mechanism with significant ligament stretching contribution. Atomic-scale analysis reveals that both structures develop dislocation-mediated plasticity initially, but ANPG transitions to localized ligament necking and fractures more rapidly, explaining its reduced ductility. Strain localization quantification, measured by atomic shear strain standard deviation, confirms the intensifier deformation concentration in ANPG at large plastic strain. These findings suggest anisotropic design as a powerful strategy for developing high-performance NPG for actuators, sensors, and catalytic systems where simultaneous mechanical robustness and functional performance are required.

Nanoporous gold (NPG) possesses excellent physical and chemical properties, exhibiting widespread application potential. To enhance its mechanical performance, this study proposes a novel NPG architecture featuring preferentially aligned pore channels (pa-NPG) and systematically compares its mechanical behavior with that of conventional homogeneous NPG (h-NPG). Using phase-field modeling and molecular dynamics simulations, we generate both structures with various solid volume fractions. Uniaxial compression tests reveal that pa-NPG achieves a comprehensive enhancement in mechanical properties. Its elastic modulus is 30%–55% higher, and its energy absorption per unit volume exceeds that of h-NPG by 6.9%–16.5%. Scaling-law analysis of elastic modulus indicates that while h-NPG follows a classical bending-dominated behavior (exponent ∼2), pa-NPG manifests a hybrid mechanism dominated by combined ligament axial compression and bending. A modified Gibson–Ashby scaling law is proposed to describe the elastic behavior of pa-NPG. During the plateau regime, pa-NPG exhibits a higher density of HCP atoms, indicating stronger stacking fault/dislocation activity, which contributes to its sustained hardening and higher plateau stress. Furthermore, the deformation of individual ligaments confirms the significantly greater contribution of ligament axial compression in pa-NPG compared to the predominantly bending-dominated response in h-NPG, providing direct microstructural evidence for its enhanced load-bearing efficiency. These microstructural responses lead to a higher plateau stress and superior specific energy absorption in pa-NPG. This work provides a promising design strategy for lightweight structural materials with tailored mechanical performance.