阅读说明：本技术 一种金属-有机配位结构的构筑方法 (Construction method of metal-organic coordination structure ) 是由 于丹 欧阳佐柃 孔惠慧 钟秦 于 2021-07-05 设计创作，主要内容包括：本发明公开了一种金属-有机配位结构的构筑方法,本发明通过在表面可控引入特定类型与浓度的金属原子以及调控分子与金属原子的比例实现了金属-有机配位结构的构筑,卤代萘酚分子与铁原子在表面共沉积并在特定温度下退火后形成具有O-Fe-O,C-Fe-C两种配位键的金属-有机配位结构,与过去只包含单一配位键的金属-有机配位结构相比,该配位结构具有更加特殊复杂的电学、磁学性质,同时该结构具有更多的反应活性位点,在催化、分子识别等领域中具有更广泛的潜在应用前景。(The invention discloses a construction method of a metal-organic coordination structure, which realizes the construction of the metal-organic coordination structure by controllably introducing metal atoms of specific types and concentrations into the surface and regulating the proportion of molecules and the metal atoms, wherein halogenated naphthol molecules and iron atoms are codeposited on the surface and annealed at a specific temperature to form the metal-organic coordination structure with two coordination bonds of O-Fe-O and C-Fe-C.)

1. A method for constructing a metal-organic coordination structure is characterized by comprising the following steps:

step 1, sequentially depositing halogenated naphthol molecules and iron atoms on the surface of a metal single crystal at room temperature to obtain a metal substrate with the halogenated naphthol molecules and the iron atoms;

and 2, annealing the metal substrate with the halogenated naphthol molecules and the iron atoms obtained in the step 1 to obtain the metal substrate with the halogenated naphthol molecules and the iron atoms.

2. The method of claim 1, wherein the halogenated naphthol molecule is 3-bromo-2-naphthol.

3. The method of claim 1, wherein the metal single crystal surface is Au (111).

4. The method according to claim 1, wherein the specific process of step 1 is as follows: filling halogenated naphthol molecules into a quartz crucible, filling the quartz crucible into a sample injection cavity, heating and sublimating the halogenated naphthol molecules, depositing the halogenated naphthol molecules on the surface of the metal single crystal, transferring a sample into a preparation cavity after the deposition of the halogenated naphthol molecules is finished, and heating and depositing metal atoms by using an iron-containing metal source to obtain the metal substrate with the halogenated naphthol molecules and the iron atoms.

5. The method of claim 1, wherein the specific process of step 2 is as follows: and heating the metal substrate with the halogenated naphthol molecules and the iron atoms from room temperature to the annealing temperature of 348K for annealing.

Technical Field

The invention relates to a construction method of a novel metal-organic coordination structure.

Background

In recent decades, molecular surface self-assembly and surface reaction have been widely applied to nanoscale surface functionalization and patterning, and thus are further applied to the fields of functional nanomaterials, organic electronics, and the like. With the development of surface science and technology, a Scanning Tunneling Microscope (STM) plays a huge role as a surface reaction observation and analysis tool, can obtain images of surface atomic arrangement and related electronic properties in real time in real space, and can be applied to surface morphology and physical and chemical phenomena related to surface electronic behaviors. By means of the accurate imaging function and the powerful spectroscopy function of the scanning tunnel microscope, the route and the back mechanism of the whole surface reaction can be more intuitively recognized.

Surface self-assembly and surface reaction are taken as feasible methods for accurately preparing the low-dimensional nano structure, and non-covalent interactions and covalent interactions such as hydrogen bonds, halogen bonds, coordination bonds, dipole interactions, van der waals forces and the like are mainly utilized to construct structures with specific functions and complex and ordered structures. The metal coordination bond has reversibility compared with a covalent bond, so that the organic metal coordination structure has certain self-repairing capability; while the strength of the coordination bond is relatively high compared to other non-covalent interactions, the organic coordination structure has a higher thermal stability than other self-assembled structures.

The organic metal coordination structure can ensure the structural stability and change along with the change of the external environment, has a large application space in electricity, catalysis, gas separation and the like, and is widely used for constructing a novel nano structure with expected functions. By surface self-assembly and surface reaction, an organometallic coordination structure with good performance can be obtained. However, the organometallic coordination structure containing only a single coordination bond has single electrical and magnetic properties, which limits the practical application of the material. Therefore, an organometallic complex structure containing a plurality of coordination bonds is required to solve the above problems.

Disclosure of Invention

In order to solve the technical problems, the invention provides a method for constructing a metal-organic coordination structure, which adopts the technical scheme that the method comprises the following steps:

step 1, sequentially depositing halogenated naphthol molecules and iron atoms on the surface of a metal single crystal at room temperature to obtain a metal substrate with the halogenated naphthol molecules and the iron atoms;

and 2, annealing the metal substrate with the halogenated naphthol molecules and the iron atoms obtained in the step 1 to obtain the metal substrate with the halogenated naphthol molecules and the iron atoms.

Further, in the step 1, the halogenated naphthol molecule is 3-bromo-2-naphthol; the surface of the metal single crystal is Au (111).

Further, in step 1, the specific steps are as follows: filling halogenated naphthol molecules into a quartz crucible, filling the quartz crucible into a sample injection cavity, heating and sublimating the halogenated naphthol molecules, depositing the halogenated naphthol molecules on the surface of the metal single crystal, transferring a sample into a preparation cavity after the deposition of the halogenated naphthol molecules is finished, and heating and depositing metal atoms by using an iron-containing metal source to obtain the metal substrate with the halogenated naphthol molecules and the iron atoms.

Further, in the step 2, the specific operation process is as follows: and heating the metal substrate with the halogenated naphthol molecules and the iron atoms from room temperature to the annealing temperature of 348K for annealing.

Compared with the prior art, the invention has the beneficial effects that: the preparation process is simple and controllable; the invention carries out reaction in an ultrahigh vacuum environment, and the product has high purity; the reaction rate of reactants on the surface is high, and the waste of raw materials is reduced; the generated metal-organic structure realizes a metal-organic coordination structure, and compared with the existing metal-organic coordination structure with a single coordination bond type, the novel metal-organic coordination structure has two metal-organic coordination bonds of O-Fe-O and C-Fe-C, and the electrical property of the structure is enriched.

Drawings

FIG. 1 is a structural formula and a model diagram of 3-bromo-2-naphthol.

FIG. 2 is an image and best model of an STM scan of 3-bromo-2-naphthol molecules of example 1 of the invention deposited on a Au (111) surface at room temperature.

FIG. 3 shows STM scan images and best mode after annealing of 3-bromo-2-naphthol molecules of example 2 of the invention deposited on the Au (111) surface with an iron atom deposition time of 60s and heating to 348K.

FIG. 4 shows STM scan images and best models after annealing with an iron atom deposition time of 80s, heating to 385K, after deposition of 3-bromo-2-naphthol molecules of example 3 of the invention onto the Au (111) surface.

Detailed Description

The present invention is further illustrated by the following figures and specific examples, which are to be understood as illustrative only and not as limiting the scope of the invention, which is to be given the full breadth of the appended claims and any and all equivalent modifications thereof which may occur to those skilled in the art upon reading the present specification.

The halogenated naphthol molecule and the iron atom are codeposited on the surface and annealed at a specific temperature to form a metal-organic coordination structure with two coordination bonds of O-Fe-O and C-Fe-C, and compared with the metal-organic coordination structure which only comprises a single coordination bond in the past, the metal-organic coordination structure has more special and complex electrical and magnetic properties, has more reactive active sites, and has wider potential application prospects in the fields of catalysis, molecular recognition and the like.

The construction method of the metal-organic coordination structure comprises the following steps:

step 1: placing an Au (111) substrate into a sample injection cavity, conveying the substrate into a preparation cavity by using a conveying rod, carrying out argon etching-annealing treatment to clean the surface of a single crystal, carrying out argon etching-annealing five times, cooling to a rated temperature, and transferring the substrate into the sample injection cavity to carry out molecular deposition.

Step 2: filling 3-bromine-2-naphthol in a quartz crucible, filling the quartz crucible into an STM sample injection cavity, heating and degassing, performing 3-bromine-2-naphthol molecular deposition on an Au (111) substrate, transferring a sample into an STM preparation cavity after the molecular deposition is completed, and performing metal atom heating deposition by using an iron-containing metal source to obtain a metal substrate with 3-bromine-2-naphthol molecules and iron atoms, wherein the structural formula and the model diagram of the 3-bromine-2-naphthol are shown in figure 1.

And step 3: and (3) annealing the metal substrate with the 3-bromine-2-naphthol molecules and the iron atoms obtained in the step (2) to obtain an annealed metal substrate.

And 4, step 4: and (3) observing the annealed metal substrate obtained in the step (2) through a scanning tunneling microscope, and after dehalogenation coupling of halogenated naphthol molecules, forming a metal-organic coordination structure through two metal-organic coordination bonds of O-Fe-O and C-Fe-C.

Example 1

Step 1: depositing 3-bromine-2-naphthol molecules on the surface of Au (111) at room temperature, wherein the deposition current is 0.4A, the deposition time is 40s, the deposition temperature is 25.1-25.3 ℃, and the substrate temperature is 298.16K-298.44K;

step 2: the formed self-assembly was observed on the surface by a Scanning Tunneling Microscope (STM), and the structure thereof was a flower-like self-assembled structure, as shown in fig. 2.

Example 2

Step 1: 3-bromine-2-naphthol molecules are deposited on the surface of Au (111), the deposition current is 0.4A, the deposition time is 3min, the deposition temperature is 25.1-25.3 ℃, and the substrate temperature is 348K;

step 2: introducing an iron metal source, depositing iron atoms on the surface of Au (111) with 3-bromine-2-naphthol molecules, wherein the deposition voltage is 1.5kV, the deposition current is 0.4A, the iron deposition time is 60s, and the deposition temperature is 25.5-26.2 ℃;

and step 3: after the deposition is finished, annealing treatment is carried out on the sample, the annealing current is 1.8A, and the annealing final temperature is 348K;

step 4: after completion of the annealing, the formation of a coordination network structure, the structural unit of which is a trimer, and a long chain was observed on the surface by a Scanning Tunneling Microscope (STM), as shown in fig. 3.

Example 3

Similar to example 2, the difference is that the deposition time in step 1 is 1.5min, the substrate temperature is 350K, the deposition temperature of iron atoms in step 2 is 25.8-26.3 ℃, the deposition time of iron atoms is 80s, the annealing temperature in step 3 is 385K, and the STM image observed in the processing step 4 is shown in fig. 4, and it can be seen that the coordination lattice structure is changed into a long chain, i.e. a novel metal-organic nanostructure formed by connecting two metal-organic coordination bonds of O-Fe-O and C-Fe-C after dehalogenation coupling of 3-bromo-2-naphthol molecules is formed.