Fig. 1: Conceptual design of dual-phase (DP) ceramic nanofiber (CNF).

a Three distinct models of DP CNFs and their differences. Model-1 represents DP CNFs fabricated by conventional methods, characterized by structural defects and uncontrolled crystal distribution. Model-2 eliminates multiscale structural defects, while Model-3 not only removes these defects but also prevents crystal aggregation. b Stress analysis and fracture mechanisms of DP CNFs under tensile and bending loads. During tensile deformation, Model-1 fractures would originate from structural defects, while Model-2 fails as a result of slip at the inner interfaces within nanocrystal clusters. In contrast, Model-3 overcomes these limitations and undergoes deformation until shear bands develop in the amorphous region, leading to fracture. During bending deformation, the fracture mechanism is dominated by localized tensile behavior on the outer side. c–d Molecular dynamics (MD) models for amorphous TiO₂ and DP TiO₂ with the color scale bar indicating the centrosymmetry parameter for each atom in the system. e Radial distribution functions for Ti−O, Ti−Ti, and O−O bonding in amorphous and DP TiO₂ models, respectively. f Construction of MD models for the amorphous structure, Model-2, and Model-3. g Snapshots at different strains (ε) during tensile simulations of Model-2 and Model-3, with the color scale bar representing the volumetric stress.