Surface plasmon enhancement in different spatial distributions of nanowires and two-dimensional materials.

Surface plasmon (SP) nanostructures have been widely researched to improve the low light absorption of two-dimensional transition metal dichalcogenides (TMDCs). However, the impact of their different coupling forms, which is essential for the optimization of nanostructures, has been rarely investigated. Here, we construct two different spatially distributed composite structures of Ag nanowires (NWs) and monolayer (1L) molybdenum disulfide (MoS2). When the Ag NW was buried under 1L MoS2, the formed tiny optical cavity can further promote the light utilization of 1L MoS2, so that the spectral enhancement by SP was stronger than that when the Ag NW was placed on the top of 1L MoS2. In addition, the photoresponsivity and light response speed of the phototransistor based on the composite structure with Ag NWs buried underneath were improved by ∼5-fold and ∼1000-fold, respectively, compared to those of the pristine 1L MoS2 phototransistor. This research provides a reference for the optimization of SP nanostructures to enhance the optoelectronic properties of two-dimensional materials.

Study on Low-Velocity Impact Damage and Residual Strength of Reinforced Composite Skin Structure.

In order to better understand the damage tolerance of reinforced composite plates, the impact damage of the reinforced composite plates was investigated under low-velocity impact test. The experimental results show that the impact of different positions and energies causes different degrees of damage to the specimens, including but not limited to ply fracture, internal delamination of the skin, and debonding of the stiffeners and skin. After impacting, the specimens were tested in an axial compression. The results show that the ultimate bearing capacity of the specimen is also affected by different forms of impact. The impact point has the greatest influence on the specimen while it locates at the intersection of longitudinal and transverse bars. Compared with the intact specimen, the ultimate load carrying capacity was reduced by 16.83% and 44.02%, while the specimen impacted by 15 J and 30 J, respectively. The compression failure mode of the damaged specimen is mainly the breakage of the stiffeners and the delamination of the skin.