Mechanical properties of fullerene embedded silicon nanowires

In order to examine the possibility of developing silicon nanowires (Si NWs) with enhanced mechanical characteristics, this study investigates the effects of fullerene integration on the mechanical characteristics of [110]-oriented Si NWs subjected to uniaxial tension by performing classical molecular dynamics simulations. For this purpose, various types of fullerenes (i.e., C₆₀, C₁₈₀, and C₃₂₀) with different weight ratios (i.e., 0.5%, 0.75%, 1.25%, and 2.5%) are randomly embedded into Si NWs with diameters of 3, 4 and 5 nm. It is demonstrated that the tensile strength, the ultimate tensile strain and Young’s modulus of fullerene-embedded Si NWs (F-Si NWs) can be enhanced up to 140.74%, 70.59% and 23.13%, respectively. Resistance to lateral contraction and blockage of crack propagation are considerable advantages of fullerenes, which significantly improves the mechanical properties of Si NWs without causing a considerable transition to amorphous phase from the cubic diamond lattice structure of bulk silicon. Furthermore, while additive-free Si NW with a diameter of 5 nm showing brittle failure at room temperature, a ductile behavior is observed at the same loading rate for the fullerene embedded NWs independently from the fullerene types and weight ratios. Considering the outstanding mechanical enhancements and their tunable characteristics, F-Si NWs might reveal promising opportunities for the next generation semiconductors.