Excitation of surface plasmons from silver nanowires embedded in polymer nanofibers

Preparation of Device-Level ZnO-Covered Silver Nanowires Films and Their Applications as Sub-Electrode for Polymer Solar Cells

Silver nanowire films are good candidates to be used as transparent conductive films that could be widely utilized in organic photoelectronic devices such as polymer solar cells. However, their application is usually limited, as they are mainly used as top electrode materials; otherwise, they would be prone to complex transferring processes. In this study, we successfully prepared device-level ZnO-covered silver nanowire (AgNWs/ZnO) films. ZnO was prepared by a spray pyrolysis method using zinc-ammonia solution at a relatively low temperature (95°C). The films showed good adhesive properties to the glass substrate, considering it withstood the process of applying polyimide tapes on the surface and tearing them off more than 100 times. It also exhibited good conductivity (∼24 Ω/sq) with high transmittance in the visible range (>80%). After a simple polish and patterning, AgNWs/ZnO showed a good performance as a sub-electrode for polymer solar cells. The PM6:Y6 devices achieved a high power conversion efficiency of 8.37% with an open-circuit voltage of 0.81 V, a short-circuit current density of 18.18 mA/cm², and a yield of 81.25%. This indicates that the technology has a good prospect of large-scale fabrication of organic photoelectronic devices.

SERS-active substrate assembled by Ag NW-embedded porous polystyrene fibers

Here we demonstrate a novel SERS-active substrate assembled by silver nanowire (Ag NW)-embedded porous polystyrene (PS) fibers. Ag NWs are synthesized through a glycerol-mediated solvothermal method firstly, then electrospun into PS porous fibers. The as-synthesized Ag NWs are embedded in PS fiber and aligned orderly along the axial direction. Porous structure appears in PS fiber due to the phase separation induced by rapid evaporation of solvents. Large amounts of holes not only greatly improve the sample collection efficiency of the SERS-active substrate, but also significantly facilitate the adsorption of target molecules on the surface of Ag NWs, thus increasing the probability of enhancement of target molecules. In addition, compared with polyvinyl alcohol (PVA) and polyvinyl pyrrolidone (PVP), PS has better solvent resistance. The detection limit of 4-aminothiophenol (4-ATP) on our fabricated electrospun fiber mats is 10⁻⁷ M, and the electrospun fiber mats showed good reproducibility of SERS signal detection. This study proposes a feasible strategy for the large-scale preparation of flexible SERS-active substrate assembled by Ag NW-embedded porous PS fibers. The produced flexible SERS substrates may have potential application in wearable sensors for the trace detection of chemical and biological molecules.

SERS-active substrate assembled by Ag NW-embedded porous PS fibers has high sample collection efficiency for the target molecule.

Thermally Stable Silver Nanowires-Embedding Metal Oxide for Schottky Junction Solar Cells

Thermally stable silver nanowires (AgNWs)-embedding metal oxide was applied for Schottky junction solar cells without an intentional doping process in Si. A large scale (100 mm(2)) Schottky solar cell showed a power conversion efficiency of 6.1% under standard illumination, and 8.3% under diffused illumination conditions which is the highest efficiency for AgNWs-involved Schottky junction Si solar cells. Indium-tin-oxide (ITO)-capped AgNWs showed excellent thermal stability with no deformation at 500 °C. The top ITO layer grew in a cylindrical shape along the AgNWs, forming a teardrop shape. The design of ITO/AgNWs/ITO layers is optically beneficial because the AgNWs generate plasmonic photons, due to the AgNWs. Electrical investigations were performed by Mott-Schottky and impedance spectroscopy to reveal the formation of a single space charge region at the interface between Si and AgNWs-embedding ITO layer. We propose a route to design the thermally stable AgNWs for photoelectric device applications with investigation of the optical and electrical aspects.

Plasmon-assisted trapping of nanoparticles using a silver-nanowire-embedded PMMA nanofiber

The integration of surface plasmon with waveguide is a strategy for lab-on-a-chip compatible optical trapping. Here, we report a method for trapping of nanoparticles using a silver nanowire (AgNW) embedded poly(methyl methacrylate) (PMMA) nanofiber with the assistance of surface plasmon polaritons (SPPs). The nanoparticles (polystyrene, 700 nm diameter) are transported along the nanofiber and ultimately trapped at the AgNW embedded region because of the enhanced optical gradient force towards the nanofiber exerted on the nanoparticles and optical potential well generated by the excitation of SPPs. The low optical power requirement and the easy fabrication of the AgNW-embedded nanofiber with broad range of wavelength for SPPs are advantageous to the applications in optofluidics and plasmofluidics.