Graphene nanoribbon / copper selenide semiconductor heterostructure and preparation method thereof

Abstract

The present application relates to a kind of graphene nanobelt / copper selenide semiconductor heterostructure and its preparation method, belong to nanometer material technical field.The present application utilizes the strategy that intermolecular carbon hydrogen activation and intramolecular cyclization dehydrogenation will occur under the catalysis of four anthracene precursor in copper substrate, four anthracene precursor molecule is deposited on copper surface, and is kept at 100 ℃-400 ℃ temperature for 30 minutes to obtain one-dimensional graphene nanobelt.Then, the strategy that single-layer copper selenide semiconductor is generated by the chemical reaction of selenium powder and copper substrate is used, by depositing selenium powder on the above graphene nanobelt and copper substrate, and keeping at 100 ℃-400 ℃ temperature for 30 minutes, to obtain graphene nanobelt / copper selenide semiconductor heterostructure.

Description

TECHNICAL FIELD

[0001] The application relates to a graphene nanoribbon / copper selenide semiconductor heterostructure and a preparation method thereof, and belongs to the technical field of nanomaterials. BACKGROUND

[0002] In recent years, van der Waals heterostructures have attracted much attention due to their potential in fundamental research and applications in the field of electronics and optoelectronics. Unlike traditional heterostructures based on covalent bonding, vertical heterostructures can combine a variety of materials together through weak van der Waals forces without any dangling bonds and are not limited by lattice matching, thus realizing flexible integration and providing great opportunities for exploring various combinations of materials and multifunctional optoelectronic devices. So far, a variety of van der Waals heterostructures have been assembled using chemical vapor deposition and molecular beam epitaxy techniques, such as molybdenum disulfide / tungsten disulfide, chromium diselenide / molybdenum diselenide, etc. However, most of the van der Waals heterostructures are focused on two-dimensional materials, and vertical heterojunctions between two-dimensional materials and other dimensional materials (such as one-dimensional carbon-based materials) are rarely reported.

[0003] One-dimensional graphene nanoribbons have attracted extensive attention in the past decade due to their interesting electronic properties and potential applications in nanoelectronic devices. In order to realize graphene nanoribbons with well-defined width and edge structure (i.e. armchair, zigzag or concave edge), two bottom-up synthesis strategies have been developed, namely surface synthesis and solution synthesis. Compared with solution-based synthesis methods, surface synthesis shows substantial advantages in characterization, such as chemical structure identification in real space and electronic structure measurement, etc. By constructing vertical heterojunctions of one-dimensional graphene nanoribbons and two-dimensional materials, the advantages of graphene nanoribbons such as tunable band gap, large width-to-height ratio and large specific surface area can be combined with the advantages of two-dimensional materials such as high active site concentration, short diffusion length and high mobility. SUMMARY

[0004] In view of the problems and deficiencies in the prior art, the application provides a graphene nanoribbon / copper selenide semiconductor heterostructure and a preparation method thereof. The application utilizes two strategies: 1. The tetraanthracene precursor will chemically react with the copper single crystal surface to form one-dimensional graphene nanoribbons; 2. The selenium powder will chemically react with the copper single crystal surface to form a compound. The tetraanthracene precursor is deposited on the surface of the copper substrate to obtain a self-assembled sample on the surface of the copper single crystal, the sample is heated to a growth temperature, and the sample is subjected to annealing treatment to obtain one-dimensional graphene nanoribbons. Then, the selenium powder is deposited on the surface of the sample, and the sample is heated to a growth temperature, and the sample is subjected to annealing treatment, and finally a graphene nanoribbon / copper selenide semiconductor heterostructure is obtained.

[0005] A graphene nanoribbon / copper selenide semiconductor heterostructure and a preparation method thereof, and the specific steps include:

[0006] Step 1, preparing a copper single crystal substrate;

[0007] Step 2, depositing a tetraanthracene precursor molecule on the copper single crystal substrate kept at room temperature through a molecular beam epitaxy technology to obtain an assembled structure of the substrate and the tetraanthracene precursor molecule;

[0008] Step 3, heating the assembled structure of the substrate and the tetraanthracene precursor molecule obtained in step 2 to 100-400 DEG C and keeping for 30 minutes to obtain a one-dimensional graphene nanoribbon;

[0009] Step 4, depositing selenium powder on the graphene nanoribbon sample in step 3 through a molecular beam epitaxy technology, heating to 100-400 DEG C and keeping for 30 minutes to obtain a graphene nanoribbon / copper selenide semiconductor heterostructure;

[0010] The preparation process of the copper single crystal substrate is specifically as follows:

[0011] Step 1.1, performing argon ion sputtering treatment on a copper substrate in an ultrahigh vacuum cavity to obtain a copper substrate;

[0012] Step 1.2, heating the copper substrate obtained in step 1.1 to 480 DEG C and keeping for 10-30 minutes to obtain a copper single crystal substrate.

[0013] The evaporation temperature of the tetraanthracene precursor molecule in step 2 is 180-190 DEG C, and the deposition time is 2-5 minutes.

[0014] The evaporation temperature of the selenium powder in step 4 is 80-90 DEG C, and the deposition time is 20-25 minutes.

[0015] The present application has the following beneficial effects:

[0016] The present application can prepare a vertical heterostructure of a graphene nanoribbon and a single-layer copper selenide. BRIEF DESCRIPTION OF DRAWINGS

[0017] Figure 1 Fig. 1 is a scanning tunneling microscope image of a one-dimensional graphene nanoribbon prepared in Example 1 of the present application;

[0018] Figure 2 Fig. 2 is a scanning tunneling microscope image of a graphene nanoribbon / copper selenide semiconductor heterostructure prepared in the present application with atomic precision. DETAILED DESCRIPTION

[0019] The present application will be further described below in combination with the drawings and specific embodiments.

[0020] Test instruments and equipment:

[0021] Low temperature scanning tunneling microscope: purchased from Omicron, Germany.

[0022] K-cell molecular evaporation source: purchased from Omicron, Germany.

[0023] Argon ion gun: purchased from Omicron, Germany.

[0024] Phase-locked amplifier: purchased from Omicron, Germany.

[0025] Raw materials:

[0026] Tetraanthracene precursor molecules: purchased from Bide Pharmatech, purity 99%.

[0027] Selenium powder: purchased from Sigma-Aldrich, purity 99.9%.

[0028] Copper single crystal: purchased from MaTecK, purity 99.999%.

[0029] Example 1

[0030] The preparation method of the graphene nanoribbon / copper selenide semiconductor heterostructure includes the following steps:

[0031] Step 1, preparing a copper single crystal substrate; the preparation process of the copper single crystal substrate is specifically as follows:

[0032] Step 1.1, performing argon ion sputtering treatment on the copper substrate in an ultrahigh vacuum cavity to obtain a copper substrate;

[0033] Step 1.2, heating the copper substrate obtained in step 1.1 to 480 DEG C and keeping the temperature for 10 minutes to obtain a copper single crystal substrate;

[0034] Step 2, evaporating and depositing 50 milligrams of tetraanthracene precursor molecules on the 50 grams of copper single crystal substrate of step 1 by using a thermal resistance type K-cell molecular evaporation source at an evaporation temperature of 185 DEG C to obtain a substrate and a self-assembled structure of the tetraanthracene precursor molecules deposited on the substrate, and the copper single crystal substrate temperature is controlled to be 30 DEG C during the deposition process, and the deposition time is 5 minutes;

[0035] Step 3, performing first temperature rising to the growth temperature for the substrate and the copper selenide compound deposited on the substrate of step 2; the growth temperature is 250 DEG C, and the temperature keeping time is 30 minutes;

[0036] Step 4, then evaporating and depositing 100 milligrams of selenium powder on the 50 grams of copper single crystal substrate treated in step 3 by using a thermal resistance type K-cell molecular evaporation source at an evaporation temperature of 85 DEG C, and the substrate and the deposit temperature is controlled to be 30 DEG C during the deposition process, and the deposition time is 25 minutes;

[0037] Step 5, the copper selenide deposit and the substrate obtained in step 4 are subjected to a second temperature rising to the growth temperature for heat preservation to obtain a graphene nanoribbon / copper selenide semiconductor heterostructure; the growth temperature is 250°C, and the heat preservation time is 30 minutes.

[0038] The scanning tunneling microscope image of the graphene nanoribbon obtained in the example is shown in FIG. 2. Figure 1 As can be seen from FIG. 2, the graphene nanoribbon is of high quality and arranged in an orderly manner. Figure 1

[0039] The scanning tunneling microscope image of the graphene nanoribbon / copper selenide semiconductor heterostructure obtained in the example is shown in FIG. 3. Figure 2

[0040] Example 2

[0041] The method for preparing the graphene nanoribbon / copper selenide semiconductor heterostructure with adjustable energy band arrangement comprises the following specific steps:

[0042] Step 1, a copper single crystal substrate is prepared; the preparation process of the copper single crystal substrate is as follows:

[0043] Step 1.1, argon ion sputtering treatment is performed on the copper substrate in an ultrahigh vacuum cavity to obtain a copper substrate;

[0044] Step 1.2, the copper substrate obtained in step 1.1 is heated to 480°C for heat preservation for 30 minutes to obtain a copper single crystal substrate;

[0045] Step 2, 50 milligrams of tetraanthracene precursor molecules are evaporated and deposited on the 50 grams of copper single crystal substrate in step 1 at an evaporation temperature of 190°C by using a thermal resistance type K-cell molecular evaporation source to obtain a substrate and a self-assembled structure of the tetraanthracene precursor molecules deposited on the substrate; the copper single crystal substrate temperature is controlled to be 30°C during the deposition process, and the deposition time is 2 minutes;

[0046] Step 3, the self-assembled sample of the tetraanthracene precursor molecules obtained in step 2 is subjected to a first temperature rising to the growth temperature for heat preservation; the growth temperature is 250°C, and the heat preservation time is 30 minutes;

[0047] Step 4, then 100 milligrams of selenium powder are evaporated and deposited on the 50 grams of substrate treated in step 3 at an evaporation temperature of 88°C by using a thermal resistance type K-cell molecular evaporation source; the substrate and the deposit temperature is controlled to be 30°C during the deposition process, and the deposition time is 20 minutes;

[0048] Step 5, the sample obtained in step 4 is subjected to a second temperature rising to the growth temperature for heat preservation to obtain a graphene nanoribbon / copper selenide semiconductor heterostructure; the growth temperature is 250°C, and the heat preservation time is 30 minutes.

[0049] Example 3​​

[0050] The method for preparing the graphene nanoribbon / copper selenide semiconductor heterostructure with tunable band arrangement includes the following specific steps:

[0051] Step 1: Preparation of copper single crystal substrate; The preparation process of copper single crystal substrate is as follows:

[0052] Step 1.1: In an ultra-high vacuum chamber, an argon ion sputtering process is performed on a copper substrate to obtain a copper substrate;

[0053] Step 1.2: Heat the copper substrate obtained in Step 1.1 to 480℃ and hold for 30 minutes to obtain a copper single crystal substrate;

[0054] Step 2: 50 mg of tetraanthracene precursor molecules were evaporated and deposited on the 50 g copper single crystal substrate from Step 1 using a thermally resistive K-cell molecular evaporation source at an evaporation temperature of 180 °C. The resulting substrate and the self-assembled structure of the tetraanthracene precursor molecules deposited on the substrate were obtained. The deposition process controlled the temperature of the copper single crystal substrate at 30 °C and the deposition time at 15 minutes.

[0055] Step 3: The self-assembled sample of the tetraanthracene precursor molecules obtained in Step 2 is heated to the growth temperature for the first time and kept at that temperature for 30 minutes.

[0056] Step 4: Then, 100 mg of selenium powder was evaporated and deposited onto a 50 g substrate treated in Step 3 at an evaporation temperature of 80 °C using a thermally resistive K-cell molecular evaporation source. The temperature of the substrate and the deposit was controlled at 30 °C during the deposition process, and the deposition time was 60 minutes.

[0057] Step 5: The sample obtained in Step 4 is heated to the growth temperature for a second time and held for 30 minutes to obtain a graphene nanoribbon / copper selenide semiconductor heterostructure.

[0058] The specific embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of the present invention.

Claims

1. A method for preparing a graphene nanoribbon / copper selenide semiconductor heterostructure, characterized in that... The specific steps include: Step 1: Prepare a copper single-crystal substrate; Step 2: Deposit tetraanthracene precursor molecules onto a copper single crystal substrate maintained at room temperature using molecular beam epitaxy to obtain the assembled structure of the substrate and tetraanthracene precursor molecules. Step 3: The assembly structure of the substrate and tetraanthracene precursor molecules obtained in Step 2 is heated to 100℃-400℃ and held for 30 minutes to obtain one-dimensional graphene nanoribbons. Step 4: Selenium powder is deposited onto the graphene nanoribbon sample described in Step 3 using molecular beam epitaxy, and the temperature is raised to 100℃-400℃ and held for 30 minutes to obtain a graphene nanoribbon / copper selenide semiconductor heterostructure.

2. The method for preparing a graphene nanoribbon / copper selenide semiconductor heterostructure according to claim 1, characterized in that... The preparation process of the copper single crystal substrate is as follows: Step 1.1: In an ultra-high vacuum chamber, an argon ion sputtering process is performed on a copper substrate to obtain a copper substrate; Step 1.2: Heat the copper substrate obtained in Step 1.1 to 480℃ and hold for 20-30 minutes to obtain a clean copper single crystal substrate.

3. The method for preparing a graphene nanoribbon / copper selenide semiconductor heterostructure according to claim 1, characterized in that: In step 2, the evaporation temperature of the tetraanthracene precursor molecules is 180℃-190℃, and the deposition time is 2 minutes-5 minutes.

4. The method for preparing a graphene nanoribbon / copper selenide semiconductor heterostructure according to claim 1, characterized in that: In step 4, the selenium powder evaporation temperature is 80℃-90℃, and the deposition time is 20 minutes-25 minutes.

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