阅读说明：本技术 一种硅片基硫化铋纳米花阵列的半导体光电材料的制备方法和应用 (Preparation method and application of semiconductor photoelectric material of silicon wafer-based bismuth sulfide nanoflower array ) 是由 蒋颖畅 孙士斌 常雪婷 王东胜 于 2020-06-01 设计创作，主要内容包括：本发明属于化工材料技术领域,具体为一种硅片基硫化铋纳米花阵列的制备方法和应用。本发明方法包括：通过简单的水热法即可在硅片基底上进行硫化铋纳米花阵列的组装,经过充分和烘干处理得到硅片基硫化铋阵列结构。硅片上生长的硫化铋纳米花晶体,形貌均一,尺寸约为800nm,化学式为Bi<Sub>2</Sub>S<Sub>3</Sub>,本发明工艺简便、具有普适性,可以制备其他硫化物。制得的硫化铋纳米花阵列,在光电检测器和场发射等领域具有巨大的应用前景。(The invention belongs to the technical field of chemical materials, and particularly relates to a preparation method and application of a silicon wafer-based bismuth sulfide nanoflower array. The method comprises the following steps: the bismuth sulfide nanoflower array can be assembled on the silicon wafer substrate through a simple hydrothermal method, and the silicon wafer substrate bismuth sulfide array structure is obtained through full and drying treatment. The bismuth sulfide nanometer flower crystal grown on the silicon chip has uniform appearance, the size of about 800nm and the chemical formula of Bi 2 S 3 The method has simple and convenient process and universality, and can be used for preparing other sulfides. The prepared bismuth sulfide nanoflower array has great application prospect in the fields of photoelectric detectors, field emission and the like.)

1. A preparation method of a silicon chip-based bismuth sulfide nanoflower array is characterized by comprising the following specific steps:

(1) cleaning, hydroxylating and surface sulfhydrylation modification of a silicon wafer: firstly, cutting a silicon wafer into a set size, respectively carrying out ultrasonic treatment for 20mins by using acetone, ethanol and deionized water in sequence, drying the silicon wafer by using a blower with cold air, and then placing the silicon wafer into a concentrated sulfuric acid solution (30% H) prepared in advance₂O₂And concentrated H₂SO₄The volume ratio is 3: 7) and (3) standing in an oven at 90 ℃ for 30nins, wherein the step is to hydroxylate the surface of the silicon wafer. After the reaction is finished, fully washing with ionized water, drying by using nitrogen, and then putting into a 2 vol% 3-MPTES solution, wherein the volume ratio of a dispersion solvent is 9: 1, adding all silicon wafers into the mixed solution of ethanol and water, dropwise adding a plurality of drops of glacial acetic acid for catalytic reaction, and sealing and standing for 24 hours at room temperature. And finally, taking out the silicon wafer modified with the sulfydryl, washing with absolute ethyl alcohol, and blowing with nitrogen flow for later use.

(2) Growth of Bi on thiolated silicon substrates by hydrothermal method₂S₃The nano flower array: first, a reaction solution was prepared by mixing 10mL of 0.1M Bi (NO)₃)₃The solution was mixed with 60mL of 0.1M NH₂CSNH₂To the solution, 1M nitric acid solution was added dropwise with stirring to adjust the pH to 0.5. And then fixing the processed silicon wafer substrate with the front side facing downwards on a customized silicon wafer fixing device, placing the silicon wafer substrate into a 100mL polytetrafluoroethylene reaction kettle inner container, and adding 70mL prepared reaction solvent. Sealing and placing in an oven at 150 ℃ for reaction for 24 h.

(3) And washing and drying to obtain the silicon wafer-based bismuth sulfide nanoflower array material.

2. The method for preparing the silicon wafer-based bismuth sulfide nanoflower array material according to claim 1, wherein the soluble salt is nitrate hydrate (Bi (NO)₃)₃·5H₂O), thiourea (NH)₂CSNH₂) The reagent is analytically pure, and all the water is deionized water; concentrated sulfuric acid and concentrated nitric acid, wherein the ethanol is commercial grade absolute ethanol, and the mass fraction is more than or equal to 99.8%.

3. The method for preparing a silicon wafer-based bismuth sulfide nanoflower array according to claim 1, wherein the method comprises two steps, wherein the first step is modification of a substrate silicon wafer, and in the process, except for the soaking and drying processes, the rest of the substrate silicon wafer is stored in a vacuum chamber and is not placed in the air for a long time; in the second step of the bismuth sulfide nanoflower array growth process, the front surface (the surface modified with sulfydryl) of the silicon wafer is ensured to face downwards, and bismuth sulfide and the like formed in the solution in the growth process are prevented from sinking on the silicon wafer. In the two-step operation process, all the silicon wafer cleaning processes are full soaking and light leaching, and all the drying processes are blown dry by using nitrogen flow.

4. The silicon wafer-based bismuth sulfide nanoflower array obtained by the production method according to claims 1 to 3.

5. The silicon wafer-based bismuth sulfide nanoflower array according to claim 4, wherein the application of the silicon wafer-based bismuth sulfide nanoflower array in a photodetector is realized by characterizing the sensitivity of the photoelectric response of the silicon wafer-based bismuth sulfide nanoflower array.

Technical Field

The invention belongs to the technical field of chemical material synthesis, and particularly relates to a preparation method of a silicon wafer-based bismuth sulfide nanoflower array semiconductor photoelectric material and application of the semiconductor photoelectric material in photoelectric detection.

Background

In recent years, the application of specially designed nano materials with various structures in a plurality of construction modules of nano devices and nano systems is more and more prominent, so people pay more and more attention to the research on the preparation process of the nano materials. The study of nanostructures also ranges from simple structures to the assembly of ordered structures, with the aim of achieving increased structural complexity and functionality. For example, a four-footed structure may be an important alternative structure for fiber and rod structures due to the multi-branched mechanical strengthening advantages, and multi-branched nanocrystals also have many advantages because they not only have all the performance characteristics of one-dimensional structural materials, but also have the advantages of hierarchical structures. However, developing a simple, novel hierarchical structure building method still has significant challenges.

Bismuth sulfide (Bi)₂S₃) Is a direct band gap semiconductor with a bandwidth Eg of 1.3 eV. The earliest reports on the photoconductive properties of bismuth sulfide were based on studies of mineral samples bismuthate in 1917. The importance of bismuth sulfide in the earliest batch of photoconductive materials was also described in 1920. Large-sized grain films of bismuth sulfide have been applied to electronic devices due to the forbidden band width of 1.25eV to 1.7 eV. Up to now, Bi₂S₃Nanoribbon, snowflake-shaped Bi₂S₃Nanorods, nanowires and nanoflowers have been successfully prepared by microwave ionic liquid methods, solvothermal methods, hydrothermal solutions and microemulsions. It can be seen, however, that most of the reactions of these methods are in solution, producing Bi₂S₃The nanomaterial is in a powder non-ordered form, and the existing form greatly limits Bi₂S₃And detecting the photoconductive characteristic of the nanostructure. Because of this, so far little can be seen about Bi₂S₃The photoelectric response nano structure is used for reporting of photoelectric devices, although the semiconductor material has good photoelectric effect, not to mention the specially constructed hierarchical structure.

The volume expansion phenomenon of different degrees not only destroys the structural stability of the electrode material and deteriorates the contact of the electrode material with an active material, but also further rapidly attenuates the capacity of the lithium ion battery. In order to better solve this problem, researchers have tried to combine a metallic negative electrode with a buffer system to eliminate the adverse effects of the volume expansion phenomenon, and sulfides have been receiving much attention as buffer materials due to their excellent mechanical and thermodynamic stability.

The invention provides a preparation method of a silicon chip-based bismuth sulfide nanoflower array with simple and convenient process and certain universality, the morphology is uniform and controllable, the crystallinity of the flaky bismuth sulfide forming the nanoflower is good, and the characterization of the photoelectric response performance of the nanoflower shows that the nanoflower has very high sensitivity to simulated sunlight. The light-induced conductivity makes it a reversible opto-electric switch, similar to an optical switch commonly used for electrical control. The array structure is shown to be used for creating a highly sensitive photoelectric detector, and an optical switch, and has a wide application prospect in the aspects of novel micro-nano electronic equipment and optoelectronic equipment.

Disclosure of Invention

Aiming at the defects in the existing synthesis technology of sulfide nano array structure materials, the invention provides a silicon chip-based bismuth sulfide nano flower array material which is simple and convenient to operate, safe and environment-friendly, a preparation method thereof and application in photoelectric detection.

The invention provides a preparation method of a silicon chip-based bismuth sulfide nanoflower array material, which comprises the following specific steps:

1. a preparation method of a silicon chip-based bismuth sulfide nanoflower array is characterized by comprising the following specific steps:

(1) cleaning, hydroxylating and surface sulfhydrylation modification of a silicon wafer, firstly cutting the silicon wafer into a set size, respectively carrying out ultrasonic treatment for 20mins by using acetone, ethanol and deionized water in sequence, blow-drying by using a blower with cold air, and then placing the silicon wafer into a concentrated sulfuric acid solution (30% H) prepared in advance₂O₂And concentrated H₂SO₄The volume ratio is 3: 7) and standing in an oven at 90 ℃ for 30mins, wherein the step is to hydroxylate the surface of the silicon wafer. After the completion of the reaction, the mixture was thoroughly washed with ionized water, blow-dried with nitrogen gas, and then placed in a 2 vol% 3-MPTES solution, and the dispersion solvent was dissolved in waterProduct ratio 9: 1, adding all silicon wafers into the mixed solution of ethanol and water, dropwise adding a plurality of drops of glacial acetic acid for catalytic reaction, and sealing and standing for 24 hours at room temperature. And finally, taking out the silicon wafer modified with the sulfydryl, washing with absolute ethyl alcohol, and blowing with nitrogen flow for later use.

(2) Growth of Bi on thiolated silicon substrates by hydrothermal method₂S₃The nano flower array: first, a reaction solution was prepared by mixing 10mL of 0.1M Bi (NO)₃)₃The solution was mixed with 60mL of 0.1M NH₂CSNH₂To the solution, 1M nitric acid solution was added dropwise with stirring to adjust the pH to 0.5. And then fixing the processed silicon wafer substrate with the front side facing downwards on a customized silicon wafer fixing device, placing the silicon wafer substrate into a 100mL polytetrafluoroethylene reaction kettle inner container, and adding 70mL prepared reaction solvent. Sealing and placing in an oven at 150 ℃ for reaction for 24 h.

(3) And washing and drying to obtain the silicon wafer-based bismuth sulfide nanoflower array material.

In the invention, the prepared silicon chip-based bismuth sulfide nanoflower array has bismuth sulfide nanoflower crystals grown on the silicon chip, uniform appearance, size of about 800nm and chemical formula of Bi₂S₃。

In the preparation method of the silicon wafer-based bismuth sulfide nanoflower array material, the soluble salt adopts hydrated nitrate (Bi (NO)₃)₃·5H₂O), thiourea (NH)₂CSNH₂) The reagent is analytically pure, and all the water is deionized water; concentrated sulfuric acid and concentrated nitric acid, wherein the ethanol is commercial grade absolute ethanol, and the mass fraction is more than or equal to 99.8%.

The preparation method of the silicon wafer-based bismuth sulfide nanoflower array is characterized by comprising two steps, wherein the first step is modification of a substrate silicon wafer, and in the process, except soaking and drying processes, other steps are stored in a vacuum box and are not placed in the air for a long time; in the second step of the bismuth sulfide nanoflower array growth process, the front surface (the surface modified with sulfydryl) of the silicon wafer is ensured to face downwards, and bismuth sulfide and the like formed in the solution in the growth process are prevented from sinking on the silicon wafer. In the two-step operation process, all the silicon wafer cleaning processes are full soaking and light leaching, and all the drying processes are blown dry by using nitrogen flow. The invention also provides application of the silicon chip-based bismuth sulfide nanoflower array in photoelectric performance.

Compared with the prior art, the invention has the technical effects that:

1. the chemical modification method and the hydrothermal synthesis process are simple and convenient and have certain universality.

2. The silicon chip-based bismuth sulfide nanoflower array obtained by the invention has the advantages that bismuth sulfide nanoflower crystals grown on the silicon chip are uniform in appearance, about 800nm in size and Bi in chemical formula₂S₃. The structure not only has the size effect of a nano-sized structure, but also has higher specific surface area and multiple active sites; meanwhile, the structure also has the synergistic effect of a stepped structure, and the nano-sheet structure assembled in a flower shape can receive light sources in different directions, so that the sensitivity of the structural material to light can be increased.

3. The single particle layer array structure is densely and uniformly arranged in an array manner, and the utilization rate and efficiency of materials are utilized to the maximum extent. The possibility and optical switch for creating highly sensitive photodetectors have great application prospects in novel micro-nano electronic and optoelectronic devices.