Controllable Arrangement Of Organic Micro-Nano Structure And Its Mechanism

Nanotechnology has attracted considerable attention in recent decades,with unprecedented progress imposing large effects in various research fields,especially in the field of photonics.With easy processability,large optical cross-section,and chemically tailorable optical property,organic optical functional materials have acted an important role in various photonic devices.More importantly,organic materials possess structure versatility and excellent material compatibility,which is very beneficial for the construction of composite nanomaterials from different photofunctional organic molecules.Compared to many of their inorganic counterparts,organic composite nanostructures could be fabricated by controlling the weak interactions between molecular units during the last ten years.However,the assembly of functional building blocks into an appropriate superstructure has not yet been developed.In this thesis,several typical organic optical functional molecules were selected to study the self-assembly of organic micro-nano structures into higher order superstructures.The construction strategy of organic superstructure structure is introduced in detail,and their growth mechanism is systematically studied.The main content includes the following two parts:（1）Controllable arrangement of Alq3 micro-nano structure:The Alq3 ellipsoidal particles were prepared by anti-solvent diffusion cooperate with solvent-volatilization induced self-assembly strategy.Meanwhile,ellipsoids experience strong long-ranged attractions to other ellipsoids when they reach the liquid-vapor interface,achieving the arrangement of ellipsoidal particles（side-to-side and tip-to-tip）.In addition,the optical waveguide behavior of ellipsoidal particles recombination structure is proposed based on the different arrangements of Alq3 ellipsoidal particles,which provides a comprehensive understanding of the functional construction of organic nanomaterials.（2）Controllable arrangement of Eu（TTA）₃phen composite aggregations:The‘Lab in a droplet’system driven by surface tension of the solution was constructed by anti-solvent self-assembly method.In this system,Eu（TTA）₃phen aggregations with low-dimensional micro/nanostructures as building block were synthesized.In addition,Eu（TTA）₃phen aggregations will form more surface defects during the formation of the Eu（TTA）₃phen aggregations due to rapid crystallization,which could provide the defect sites to induce the growth of Eu（TTA）₃phen.Eventually,the Eu（TTA）₃phen molecules nucleate and grow specifically adjacent to the ends of the aggregation structures to form another aggregation composite structures,achieving the controllable arrangement of Eu（TTA）₃phen aggregation composite structures.