Final Report Summary - INFIBRENANOSTRUCTURE (Fabrication and characterization of dielectric encapsulated millions of ordered kilometer-long nanostructures and their applications)
We revealed an unusual, complementary top-down nanowire fabrication technique to produce indefinitely long semiconducting, polymer and metallic nanowires, nanotubes and nanorods. The extended lengths of fiber-embedded nanowires and nanotubes were obtained via a process of iterative thermal co-drawing of compatible materials inside a suitable glassy matrix. In summary, the new approach has potential to draw attention as a general top down fabrication method in nanotechnology. Below, we put outcomes of our iterative size reduction (ISR) technique in context by reviewing some recent achievements.
A novel nanofabrication approach called the ISR technique was utilized to obtain a number of nanostructures and to increase its potential applicability on different areas. This technique relies on heat treatment mechanism using a high temperature furnace equipped with computerized control unit. The technique also provides the successful fabrication of architectures that are challenging to be produced using present top-down and bottom-up fabrication approaches. The ISR technique inherits all advantageous features to nanostructures fabricated by this useful strategy.
We also demonstrated ISR technique with including additional step of film doping and doped preform
preparation for the fabrication of functional fibers. This new technique was used for the production of Si-Nc doped luminescent polymer nano-fibers and magnetic Fe3O4 nanoparticles-doped polycarbonate (PC) fibers. Si-Nc doped luminescent polymer nano-fibers are more functional due to simple handling, alignment ability and luminescent stability. Magnetic Fe3O4 nanoparticles-doped polycarbonate (PC) fibers which exhibit an efficient magnetic response even against to a simple magnet and conductive polyethylene (CPE)/Multi-walled Carbon Nanotube (MWCNT) composite films.
By using the ISR-produced nanostructures we demonstrate some important optical characteristics of small scale structures such as non-resonant Mie (NRM) scattering effect. This effect observed on polymeric nanowires is notable and implemented to obtain nanohole/nanogratings
without the need of photomask, effective light accumulator for thin-film and nanowire-based
photovoltaics systems and etc. We successfully showed the potential of the ISR technique for the configuration of all-polymer solid-core bio-inspired photonic crystals.
Another technological advancement is conducted on wearable nanogenerator fabrics based on triboelectric energy harvesting using multi-material nanowire bundle fabricated by the ISR technique. The multi-material nanowire bundle contained metal electrodes and different types of dielectrics including PVDF and polyester. This was the first demonstration of chalcogenide 1D structures with a potential to work as an electrostatic energy generator. Using the ISR technique, core-shell nanostructures (Polyethersulfone (PES) is in the core and As2Se3 in the shell) were produced for triboelectric nanogenerator application. The device has shown to power parallel connected 38 LEDs simultaneously due to generation of maximum 1.23 mW DC and 0.51 W peak power.
Another important result accomplished is kilometer-long, endlessly parallel, spontaneously piezoelectric and thermally stable poly vinylidene floride (PVDF) and Poly(vinylidene floride)-tri(floraethylene) (PVDF-TrFE) micro and nanoribbons produced using the ISR technique. High piezoelectric micro and nanoribbons without electrical poling process were obtained due to high stress and temperature used in thermal drawing process. Structural analysis showed that micro and nanoribbons are thermally stable since the piezoelectric properties were preserved even after exposing to heat treatment above to the melting point. Phase transition mechanism is investigated and to our best knowledge, we measured record-high piezoelectric constant, –58.5 pm/V, from a single PVDF nanoribbon.
Finally, we showed that the ISR technique can be used for the preparation of surface textured polymer micro-fibers in kilometers length scale that have perfectly aligned micro-structures on their surfaces for anisotropic non-wetting surfaces. Fiber surfaces were spray coated with organically modified silica nanoparticles so as to provide superhydrophobicity in addition to the anisotropic behavior. The contact angle and roll-off angle measurements in both parallel and perpendicular directions to the fibers' orientation were resulted in the anisotropic wetting/non-wetting characteristics of the surfaces. Utilizing structured fibers as building blocks, we created track designs to reveal the promising potential of the surface textured fibers in the area of droplet manipulation.
A novel nanofabrication approach called the ISR technique was utilized to obtain a number of nanostructures and to increase its potential applicability on different areas. This technique relies on heat treatment mechanism using a high temperature furnace equipped with computerized control unit. The technique also provides the successful fabrication of architectures that are challenging to be produced using present top-down and bottom-up fabrication approaches. The ISR technique inherits all advantageous features to nanostructures fabricated by this useful strategy.
We also demonstrated ISR technique with including additional step of film doping and doped preform
preparation for the fabrication of functional fibers. This new technique was used for the production of Si-Nc doped luminescent polymer nano-fibers and magnetic Fe3O4 nanoparticles-doped polycarbonate (PC) fibers. Si-Nc doped luminescent polymer nano-fibers are more functional due to simple handling, alignment ability and luminescent stability. Magnetic Fe3O4 nanoparticles-doped polycarbonate (PC) fibers which exhibit an efficient magnetic response even against to a simple magnet and conductive polyethylene (CPE)/Multi-walled Carbon Nanotube (MWCNT) composite films.
By using the ISR-produced nanostructures we demonstrate some important optical characteristics of small scale structures such as non-resonant Mie (NRM) scattering effect. This effect observed on polymeric nanowires is notable and implemented to obtain nanohole/nanogratings
without the need of photomask, effective light accumulator for thin-film and nanowire-based
photovoltaics systems and etc. We successfully showed the potential of the ISR technique for the configuration of all-polymer solid-core bio-inspired photonic crystals.
Another technological advancement is conducted on wearable nanogenerator fabrics based on triboelectric energy harvesting using multi-material nanowire bundle fabricated by the ISR technique. The multi-material nanowire bundle contained metal electrodes and different types of dielectrics including PVDF and polyester. This was the first demonstration of chalcogenide 1D structures with a potential to work as an electrostatic energy generator. Using the ISR technique, core-shell nanostructures (Polyethersulfone (PES) is in the core and As2Se3 in the shell) were produced for triboelectric nanogenerator application. The device has shown to power parallel connected 38 LEDs simultaneously due to generation of maximum 1.23 mW DC and 0.51 W peak power.
Another important result accomplished is kilometer-long, endlessly parallel, spontaneously piezoelectric and thermally stable poly vinylidene floride (PVDF) and Poly(vinylidene floride)-tri(floraethylene) (PVDF-TrFE) micro and nanoribbons produced using the ISR technique. High piezoelectric micro and nanoribbons without electrical poling process were obtained due to high stress and temperature used in thermal drawing process. Structural analysis showed that micro and nanoribbons are thermally stable since the piezoelectric properties were preserved even after exposing to heat treatment above to the melting point. Phase transition mechanism is investigated and to our best knowledge, we measured record-high piezoelectric constant, –58.5 pm/V, from a single PVDF nanoribbon.
Finally, we showed that the ISR technique can be used for the preparation of surface textured polymer micro-fibers in kilometers length scale that have perfectly aligned micro-structures on their surfaces for anisotropic non-wetting surfaces. Fiber surfaces were spray coated with organically modified silica nanoparticles so as to provide superhydrophobicity in addition to the anisotropic behavior. The contact angle and roll-off angle measurements in both parallel and perpendicular directions to the fibers' orientation were resulted in the anisotropic wetting/non-wetting characteristics of the surfaces. Utilizing structured fibers as building blocks, we created track designs to reveal the promising potential of the surface textured fibers in the area of droplet manipulation.