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CN-122011452-A - One-dimensional pyrene-based organic framework nonlinear optical material, and preparation and application thereof

CN122011452ACN 122011452 ACN122011452 ACN 122011452ACN-122011452-A

Abstract

The invention relates to a one-dimensional pyrenyl organic framework nonlinear optical material, and preparation and application thereof. The material is prepared from pyrenyl amino monomer (Py) and different dialdehyde monomers (PTDE, PTBE, PDA) by directly carrying out Schiff base condensation reaction under solvothermal conditions, a series of one-dimensional linear organic framework material (COF) chain segments are constructed, and the material is further prepared into a film material. The obtained material has high ordered crystallinity, expanded pi-conjugated skeleton and obvious donor-acceptor (D-A) charge transfer channel. The invention realizes the remarkable Reverse Saturation Absorption (RSA) effect of one-dimensional pyrenyl D-A COF (Py-PTDE, py-PTBE, py-PDA) under the excitation of femtosecond laser (800 nm, 1550 nm) for the first time. In particular Py-PTDE materials, whose effective nonlinear absorption coefficients (β eff ) reach 116.89 cm ·gw ‑1 and 337.03 cm ·gw ‑1 at 800 nm and 1550 nm, respectively, are not only significantly better than precursor materials and other two COF materials, but also exhibit lower optical clipping thresholds in the near-infrared band. This excellent performance results mainly from more efficient D-a interactions within it, a narrower optical bandgap, and more efficient intramolecular charge transfer channels. The preparation method of the material is simple and has high repeatability, and the obtained COF film has excellent thermal stability and optical stability, and can be directly used for preparing optical limiting devices, ultrafast optical response devices and other three-order nonlinear optical fields.

Inventors

  • ZHANG CHI
  • CHEN LU
  • FU LULU

Assignees

  • 同济大学

Dates

Publication Date
20260512
Application Date
20260302

Claims (10)

  1. 1. The preparation method of the one-dimensional pyrene-based organic framework nonlinear optical material is characterized by comprising the following steps of: (1) Respectively weighing pyrenyl monomers 4,4' ',4' ' ' - (pyrene-1, 3,6, 8-tetrayl) tetraaniline (Py) and dialdehyde monomers 1, 10-phenanthroline-2, 9-dicarboxaldehyde (PTDE), 2, 9-bis [ P- (formyl) phenyl ] -1, 10-Phenanthroline (PTBE) and 2, 6-Pyridine Dicarboxaldehyde (PDA), mixing amine and aldehyde, dispersing and dissolving in an organic solvent, and adding an aqueous solution of acetic acid after ultrasonic treatment for 10 minutes; (2) Transferring the reaction solution in the step (1) into a glass tube for sealing, putting the glass tube into an oven, heating for reaction, washing, and drying to obtain a target product; (3) Dispersing the product obtained in the step (2) in an organic solvent, adding polymethyl methacrylate (PMMA), heating and stirring to obtain a uniform dispersion, spin-coating the obtained dispersion on a substrate, putting the substrate into a vacuum drying oven, and heating and drying to obtain the homogeneous film material for nonlinear optical testing.
  2. 2. The preparation method of the one-dimensional pyrenyl organic framework nonlinear optical material according to claim 1, wherein in the step (1), the addition molar mass ratio of the dialdehyde monomer to the pyrenyl monomer is 1:2-4.
  3. 3. The preparation method of the one-dimensional pyrenyl organic framework nonlinear optical material according to claim 1, wherein in the step (1), a solvent for dissolving pyrenyl monomers and dialdehyde monomers is composed of o-dichlorobenzene and n-butanol, and the volume ratio of the o-dichlorobenzene to the n-butanol is 1:2-4.
  4. 4. The preparation method of the one-dimensional pyrenyl organic framework nonlinear optical material according to claim 1, wherein in the step (1), the concentration of the acetic acid aqueous solution is 6-12 mol L -1 , and the volume ratio of the acetic acid aqueous solution to the total solvent of the dispersion monomers is 1:5-10.
  5. 5. The method for preparing a one-dimensional pyrenyl organic framework nonlinear optical material according to claim 1, wherein in the step (2), the reaction glass tube is degassed in a liquid nitrogen bath through three continuous freezing-vacuumizing-thawing cycles, and then is sealed by flame, wherein the reaction temperature is 100-130 ℃, and the reaction time is 72-120 hours.
  6. 6. The method for preparing the one-dimensional pyrenyl organic framework nonlinear optical material according to claim 1, wherein in the step (2), the washing process is that tetrahydrofuran, methanol, ethanol and deionized water are sequentially used for repeated washing until the washing liquid is clear and colorless. The drying temperature is 60-80 ℃.
  7. 7. The preparation method of the one-dimensional pyrenyl organic framework nonlinear optical material according to claim 1, wherein in the step (3), the dispersion liquid is N, N-dimethylformamide, the dispersion method is ultrasonic dispersion, the concentration of COF in the dispersion liquid is 1-2 mg mL -1 , the concentration of PMMA is 2-2.5 g mL -1 , the reaction temperature is 60-80 ℃, and the reaction time is 6-12 h.
  8. 8. The preparation method of the one-dimensional pyrenyl organic framework nonlinear optical material according to claim 1, wherein in the step (3), the rotating speed is 100 rpm, the heating and drying temperature is 60-80 ℃ and the time is 12-24 hours.
  9. 9. The one-dimensional pyrenyl organic framework nonlinear optical material of claim 1, which is characterized by being used for construction of an ultrafast laser response thin film device.
  10. 10. The one-dimensional pyrenyl organic frame nonlinear optical material of claim 9, wherein the ultra-fast laser response device is suitable for an ultra-fast broadband laser band of 800-1600 nm.

Description

One-dimensional pyrene-based organic framework nonlinear optical material, and preparation and application thereof Technical Field The invention belongs to the technical field of nonlinear optics, and relates to a one-dimensional pyrenyl organic framework nonlinear optical material, and preparation and application thereof. Background Covalent Organic Frameworks (COFs) are a class of crystalline porous materials formed from organic building blocks linked by reversible covalent bonds. In recent years, light weight, high structural designability, large specific surface area and excellent chemical and thermal stability have been attracting attention in the fields of photocatalysis, gas adsorption, energy storage and photonics. Particularly in optical applications, the pi conjugated structure of COF can achieve efficient light absorption and electron delocalization, making it an important candidate system for the development of new generation nonlinear optical materials. However, currently, nonlinear optical research on COF is mainly focused on two-dimensional and three-dimensional structures. Two-dimensional COFs generally rely on interlayer pi-pi stacking to construct electron coupling paths, but strong interlayer interactions tend to result in reduced dispersibility, and random slippage between layers can cause discontinuous charge channels, thereby limiting third-order nonlinear response. In addition, the synthesis of two-dimensional COFs often requires stringent solvent systems and reaction conditions, resulting in greater difficulty in structural regulation. The three-dimensional COF is formed by connecting polyhedral units in space, and the three-dimensional conjugated path is difficult to realize effective three-dimensional conjugated electron delocalization, and the optical band gap regulating capability is limited, so that the performances of reverse saturation absorption, laser limiting and the like are generally weaker than those of two-dimensional conjugated system materials. In contrast, the one-dimensional COF has unique structural advantages as a novel topological structure which appears in recent years, wherein (1) a one-dimensional chain segment regularly extends along a certain direction to form a linear channel with highly oriented functional groups, which is favorable for electron coupling and exciton migration, (2) the linear structure avoids the problem of pi-pi accumulation between strong layers in the two-dimensional COF, so that the obtained material has better dispersibility and processability, and (3) a donor-acceptor (D-A) structure can be arranged along the chain direction to exert the function of intramolecular charge transfer (intramolecular CHARGE TRANSFER, ICT) to the greatest extent, thereby reducing the band gap, enhancing the light absorption and improving the third-order polarization rate. On the other hand, constructing a D-A conjugate network with ICT strong characteristics is an effective strategy for improving third-order nonlinear response. The pyrenyl molecule is used as a high conjugated plane aromatic ring, has excellent electron donating ability, rigid skeleton and stable excited state property, and is widely used in fluorescent materials and optical functional materials. There have been studies mainly focused on the application of pyrenyl molecules in two-dimensional COF or small molecule systems, and the construction of a one-dimensional pyrenyl D-a COF structure in regular arrangement has not been used in the nonlinear optical field. In recent years, researchers mostly prepare COF into a film to improve its nonlinear optical properties, wherein doping COF with organic polymer is a better strategy, which requires COF materials to have good dispersibility in solvents, and interlayer interactions of one-dimensional COF are weak, which can meet the requirement compared with two-dimensional/three-dimensional COF. The present invention has been made in view of the above background. Disclosure of Invention The invention aims to overcome the defects of the prior art and provide a one-dimensional pyrenyl organic framework nonlinear optical material and preparation and application thereof, and aims to solve the problems of poor dispersibility, limited band gap adjustability, difficult post-processing into a film and the like of the traditional COF in nonlinear optical application. The material is further prepared into a thin film device, shows excellent nonlinear optical reverse saturation absorption response under ultra-fast laser excitation, and can be further used in the fields of optical integration and the like. The aim of the invention can be achieved by the following technical scheme: One of the technical schemes of the invention provides a preparation method of a one-dimensional pyrenyl organic framework nonlinear optical material, which comprises the following steps: (1) Weighing monomers 4,4' ',4' ' ' - (pyrene-1, 3,6, 8-tetrayl) tetraaniline (Py) and a dialdehyd