Assembly And Property Of One-dimensional Nanowires At Interfaces

Compared with traditional materials, one-dimensional nanomaterials have many different performances because of their small size effect, showing promising applications in many fields such as electronics, photoelectricity and biology. Highly controllable assembly techniques have been widely used for self-assembly of one-dimensional nanomaterials. So far researchers have proposed many assembly method, including evaporation-induced technique, external-filed-induced technique, template-induced technique, flow-assisted alignment, bubble-blown technique, and assembly on interface, etc. Each method has its own advantages and disadvantages, a feasible method should be chosen to achieve the desired effect. By assembly, improving intrinsic properties of wire-like nanostructures and obtain new performances which are not found in unassembled ones.In this dissertation, we focus on the assembly on the liquid-liquid and gas-liquid interface by Pickering emulsion and Langmuir-Blodgett methods, as well as the fabrication of functional devices. The results of research are summarized as follows: 1. In a Pickering emulsion system, hydrophilic ultrathin tellurium nanowires which synthesized by a hydrothermal method reported before can be coiled into nanorings at the oil/water interface. What is more, the influence of diameter and rigidity of nanowires on assembly has also be studied. It's notable that the choice of different emulsifiers has important influence on the result of assembly. In conclusion, we develop a simple pathway to assemble materials at interface in Pickering emulsion besides zero-dimensional nanostructures.2. A flexible, transparent electrode can be fabricated by assembling Ag nanowires network on gas/liquid interface. First, we co-assemble two kinds of nanowires (Ag nanowires and CaCO3 nanowires which extracted from natural clamshell) by Langmuir-Blodgett technique without any extra hydrophobic pretreatment. Followed by etching CaCO3 nanowires away with acetic acid, Ag nanowire networks with controllable pitch could be obtained. Subsequently by transferring these networks to polyvinyl alcohol (PVA) substrate by spin-coating technique, we fabricate super-flexible transparent electrodes of which conductivity and optical transmittance could be balanced by tuning the pitch of Ag nanowire networks. Meanwhile, the flexibility and stability of these electrodes also has been studied, after more than 1000 bending cycles, the sheet resistances almost remain the same.3. ZnO/graphene composites can be synthesized by in-situ growing ZnO nanoparticles on p-Phenylenediamine (PPD)-modified graphene. ZnO nanoparticles with a diameter of?4 nm has uniform morphology and distribution on graphene. The influence of reacting time, concentrations of reactants, different kinds of precursors and solvents on the synthesis of the composites has been discussed. Furthermore, we investigated the antibacterial activity of the film device made of ZnO/graphene composites.