Graphene nanobelt / copper selenide semiconductor heterostructure and preparation method thereof

Abstract

The invention relates to a graphene nanobelt / copper selenide semiconductor heterostructure and a preparation method thereof, and belongs to the technical field of nano materials. According to the preparation method, the strategy that tetraanthracene precursor can generate intermolecular hydrocarbon activation and intramolecular cyclization dehydrogenation under the catalytic action of a copper substrate is utilized, tetraanthracene precursor molecules are deposited on the surface of copper, and heat preservation is carried out for 30 minutes at the temperature of 100-400 DEG C to obtain the one-dimensional graphene nanobelt. Then selenium powder is deposited on the graphene nanobelt and the copper substrate, heat preservation is conducted for 30 minutes at the temperature of 100-400 DEG C, and the graphene nanobelt / copper selenide semiconductor heterostructure is obtained by means of the strategy that the selenium powder and the copper substrate are subjected to a chemical reaction to generate a single-layer copper selenide semiconductor.

Description

Technical Field

[0001] The invention relates to a graphene nanoribbon / copper selenide semiconductor heterostructure and a preparation method thereof, belonging to the technical field of nanomaterials. Background Art

[0002] In recent years, van der Waals heterostructures have attracted much attention due to their potential for fundamental research and applications in electronics and optoelectronics. Unlike traditional heterostructures based on covalent bonding, vertical heterostructures can combine multiple materials together through weak van der Waals forces without any dangling bonds and are not restricted by lattice matching, thereby achieving flexible integration and providing great opportunities for exploring various combinations of multiple 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 van der Waals heterostructures are concentrated between two-dimensional materials, while vertical heterojunctions of two-dimensional materials with 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. To achieve graphene nanoribbons with precisely defined width and edge structures (i.e., armchair, zigzag, or concave edges), two bottom-up synthetic strategies, namely, surface synthesis and solution synthesis, have been developed. Compared with solution-based synthetic methods, surface synthesis shows substantial advantages in characterization, such as chemical structure identification and electronic structure measurement in real space. By constructing vertical heterojunctions of one-dimensional graphene nanoribbons with two-dimensional materials, the advantages of graphene nanoribbons, such as tunable band gap, large aspect 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 of the invention

[0004] In view of the problems and shortcomings of the above-mentioned prior art, the present invention provides a graphene nanoribbon / copper selenide semiconductor heterostructure and a preparation method thereof. The present invention utilizes two strategies: 1. The tetraanthracene precursor will chemically react on the surface of the copper single crystal to form a one-dimensional graphene nanoribbon; 2. Selenium powder will chemically react with the surface of the copper single crystal 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, and the sample is heated to the growth temperature and then annealed to obtain a one-dimensional graphene nanoribbon. Selenium powder is then deposited on the sample surface, and the sample is heated to the growth temperature and then annealed to finally obtain a graphene nanoribbon / copper selenide semiconductor heterostructure.

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

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

[0007] Step 2, depositing the tetraanthracene precursor molecules onto a copper single crystal substrate maintained at room temperature by molecular beam epitaxy technology to obtain an assembly structure of the substrate and the tetraanthracene precursor molecules;

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

[0009] Step 4, depositing selenium powder onto the graphene nanoribbon sample described in step 3 by molecular beam epitaxy technology, heating to 100° C.-400° C., and keeping the temperature 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, in an ultra-high vacuum chamber, subjecting a copper substrate to argon ion sputtering treatment to obtain a copper base;

[0012] Step 1.2: Heat the copper substrate obtained in step 1.1 to 480° C. and keep it warm for 10-30 minutes to obtain a copper single crystal substrate.

[0013] In step 2, the evaporation temperature of the tetraanthracene precursor molecules is 180° C.-190° C., and the deposition time is 2 minutes-5 minutes.

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

[0015] The beneficial effects of the present invention are:

[0016] The invention can prepare a vertical heterostructure of graphene nanoribbons and single-layer copper selenide. BRIEF DESCRIPTION OF THE DRAWINGS

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

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

[0019] The present invention will be further described below in conjunction with the accompanying drawings and specific implementation methods.

[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 material:

[0026] Tetraanthracene precursor molecule: purchased from Bid Pharmaceuticals, 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 comprises 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, in an ultra-high vacuum chamber, subjecting a copper substrate to argon ion sputtering treatment to obtain a copper base;

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

[0034] Step 2, 50 mg of tetraanthracene precursor molecules are evaporated at 185° C. using a thermal resistance K-cell molecular evaporation source and deposited on the 50 g copper single crystal substrate in step 1 to obtain a self-assembled structure of the substrate and the tetraanthracene precursor molecules deposited on the substrate. The temperature of the copper single crystal substrate is controlled to be 30° C. during the deposition process, and the deposition time is 5 minutes;

[0035] Step 3, heating the substrate in step 2 and the copper selenium compound deposited on the substrate to a growth temperature for the first time, wherein the growth temperature is 250° C. and the temperature is kept for 30 minutes;

[0036] Step 4, then 100 mg of selenium powder is evaporated and deposited on the 50 g copper single crystal substrate treated in step 3 using a thermal resistance K-cell molecular evaporation source at an evaporation temperature of 85° C. During the deposition process, the temperature of the substrate and the deposit is controlled at 30° C., and the deposition is performed for 25 minutes;

[0037] Step 5: The copper selenide deposit and the substrate obtained in step 4 are heated to the growth temperature for a second time and kept warm to obtain a graphene nanoribbon / copper selenide semiconductor heterostructure; the growth temperature is 250° C. and the temperature is kept warm for 30 minutes.

[0038] The scanning tunneling microscope image of the graphene nanoribbon prepared in this example is as follows: Figure 1 As shown, from Figure 1 High-quality, neatly aligned graphene nanoribbons can be seen.

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

[0040] Example 2

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

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

[0043] Step 1.1, in an ultra-high vacuum chamber, subjecting a copper substrate to argon ion sputtering treatment to obtain a copper base;

[0044] Step 1.2, heating the copper substrate obtained in step 1.1 to 480° C. and keeping the temperature for 30 minutes to obtain a copper single crystal substrate;

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

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

[0047] Step 4, then 100 mg of selenium powder is evaporated and deposited on the 50 g substrate treated in step 3 using a thermal resistance K-cell molecular evaporation source at an evaporation temperature of 88° C. During the deposition process, the temperature of the substrate and the deposit is controlled at 30° C., and the deposition is performed for 20 minutes;

[0048] Step 5: The sample obtained in step 4 is heated to the growth temperature for a second time and kept warm to obtain a graphene nanoribbon / copper selenide semiconductor heterostructure; the growth temperature is 250° C. and the temperature is kept warm for 30 minutes.

[0049] Example 3

[0050] The preparation method of the graphene nanoribbon / copper selenide semiconductor heterostructure with adjustable energy band arrangement comprises the following specific steps:

[0051] Step 1: preparing a copper single crystal substrate; the preparation process of the copper single crystal substrate is specifically as follows:

[0052] Step 1.1, in an ultra-high vacuum chamber, subjecting a copper substrate to argon ion sputtering treatment to obtain a copper base;

[0053] Step 1.2, heating the copper substrate obtained in step 1.1 to 480° C. and keeping the temperature for 30 minutes to obtain a copper single crystal substrate;

[0054] Step 2, 50 mg of tetraanthracene precursor molecules are evaporated at 180° C. using a thermal resistance K-cell molecular evaporation source and deposited on the 50 g copper single crystal substrate in step 1 to obtain a self-assembled structure of the substrate and the tetraanthracene precursor molecules deposited on the substrate. The temperature of the copper single crystal substrate is controlled to be 30° C. during the deposition process, and the deposition time is 15 minutes;

[0055] Step 3, heating the self-assembled sample of the tetraanthracene precursor molecules obtained in step 2 to the growth temperature for the first time and heat preservation treatment; the growth temperature is 250° C. and the temperature is kept for 30 minutes;

[0056] Step 4, then 100 mg of selenium powder was evaporated and deposited on the 50 g substrate treated in step 3 using a thermal resistance K-cell molecular evaporation source at an evaporation temperature of 80° C. The temperature of the substrate and the deposit was controlled at 30° C. during the deposition process, and the deposition lasted for 60 minutes;

[0057] Step 5: The sample obtained in step 4 is heated to the growth temperature for a second time and kept warm to obtain a graphene nanoribbon / copper selenide semiconductor heterostructure; the growth temperature is 250° C. and the temperature is kept warm for 30 minutes.

[0058] The specific implementation modes of the present invention are described in detail above in conjunction with the accompanying drawings, but the present invention is not limited to the above implementation modes, and various changes can be made within the knowledge scope of ordinary technicians in this field without departing from the purpose of the present invention.

Claims

1. A graphene nanoribbon / copper selenide semiconductor heterostructure and a preparation method thereof, characterized in that The specific steps include: Step 1, preparing a copper single crystal substrate; Step 2, depositing the tetraanthracene precursor molecules onto a copper single crystal substrate maintained at room temperature by molecular beam epitaxy technology to obtain an assembly structure of the substrate and the tetraanthracene precursor molecules; Step 3, heating the assembled structure of the substrate and the tetraanthracene precursor molecules obtained in step 2 to 100° C.-400° C. and keeping the temperature for 30 minutes to obtain a one-dimensional graphene nanoribbon; Step 4: depositing selenium powder onto the graphene nanoribbon sample described in step 3 by molecular beam epitaxy technology, heating to 100° C.-400° C., and keeping the temperature for 30 minutes to obtain a graphene nanoribbon / copper selenide semiconductor heterostructure.

2. A graphene nanoribbon / copper selenide semiconductor heterostructure and a preparation method thereof according to claim 1, characterized in that The preparation process of the copper single crystal substrate is specifically as follows: Step 1.1, in an ultra-high vacuum chamber, subjecting a copper substrate to argon ion sputtering treatment to obtain a copper base; Step 1.2: Heat the copper substrate obtained in step 1.1 to 480°C and keep it warm for 20-30 minutes to obtain a clean copper single crystal substrate.

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

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

Images