Van der waals tellurium NANO material having broad-spectrum bulk photovoltaic response, preparation method therefor and use thereof, and photoelectric device and preparation method therefor

Abstract

The present invention relates to the technical field of photoelectric materials and devices, and particularly relates to a van der Waals tellurium nano material having bulk photovoltaic response, a preparation method therefor and the use thereof, and a photoelectric device and a preparation method therefor. The present invention provides a preparation method for a van der Waals tellurium nano material, which method comprises the following steps: using tin telluride as a raw material, and performing chemical vapor deposition on the surface of a substrate to obtain a van der Waals tellurium nano material, wherein the chemical vapor deposition is performed under a condition of introducing nitrogen. The van der Waals tellurium nano material prepared by means of the preparation method enables the bulk photovoltaic response of a photoelectric device to have a very broad spectrum band and high photocurrent density.

Description

Van der Waals tellurium nanomaterial with wide-band photovoltaic response and preparation method and application thereof, and photoelectric device and preparation method thereof TECHNICAL FIELD

[0001] The present application relates to the technical field of photoelectric materials and devices, and particularly relates to a van der Waals tellurium nanomaterial with wide-band photovoltaic response and a preparation method and application thereof, and a photoelectric device and a preparation method thereof. BACKGROUND

[0002] High-efficiency photoelectric conversion is crucial in many applications such as imaging, free-space communication and clean energy. As a second-order optical effect, bulk photovoltaic effect has attracted extensive attention of researchers due to its great potential in breaking through the Shockley-Queisser limit inherent in traditional p-n junction photovoltaic effect.

[0003] Bulk photovoltaic effect was first observed in ferroelectric oxide materials (such as LiNbO3, BaTiO3 and Pb(Zr x Ti 1-x )O3), which breaks the limitation of crystal band structure in traditional photovoltaic materials and opens up a new direction for researchers to conduct extensive research in various materials. In addition to ferroelectric oxide materials, researchers have also conducted in-depth studies on ferroelectric superlattices, perovskite halides, organic crystals, semimetals and van der Waals materials. Notably, van der Waals materials with low dimensionality, strong symmetry breaking and high strain compatibility exhibit excellent bulk photovoltaic effect. For example, in-plane tensile strain breaks the inversion symmetry of rhombohedral MoS2, resulting in a bulk photovoltaic response current of up to 10A·cm -2 at 630 nm illumination.

[0004] Due to band-to-band optical transitions in semiconductors and heterostructures, current bulk photovoltaic responses are mainly concentrated in a limited wavelength range from ultraviolet to visible light. Although the Berry curvature and scattering of semimetals can produce mid-infrared bulk photovoltaic responses, the low probability of photoelectric transition generated by polarized single-wavelength laser results in a significant decrease in photoelectric current density of bulk photovoltaic response under the same optical power. Therefore, how to realize wide-band and high photoelectric current density bulk photovoltaic response is a problem to be solved. SUMMARY

[0005] The present application aims to provide a van der Waals tellurium nanomaterial with wide-band photovoltaic response and a preparation method and application thereof, and a photoelectric device and a preparation method thereof. The van der Waals tellurium nanomaterial prepared by the preparation method can make the bulk photovoltaic response of the photoelectric device have a very wide band and high photoelectric current density.

[0006] In order to achieve the above-mentioned application purposes, the present application provides the following technical solutions:

[0007] The application provides a preparation method of van der Waals tellurium nanomaterial.

[0008] The van der Waals tellurium nanomaterial is obtained by chemical vapor deposition on the surface of the substrate with tin telluride as raw material.

[0009] The chemical vapor deposition is carried out under the condition of nitrogen.

[0010] Since each Te atom in the van der Waals tellurium nanomaterial is covalently bonded with two nearest neighbors (i.e. Te atoms) to form a helical chain. The Te helical chain is surrounded and stacked by other six Te helical chains and combined into a hexagonal structure through weak van der Waals force. Such Te belongs to a non-centrosymmetric P21 space group, and the non-symmetry center will lead to a bulk photovoltaic effect. The van der Waals tellurium nanomaterial prepared by the preparation method has high crystal quality and stronger spatial asymmetry, and thus exhibits more excellent bulk photovoltaic effect.

[0011] Preferably, the substrate comprises at least one of a silicon substrate, a glass substrate, a mica substrate and a sapphire substrate.

[0012] The thickness of the substrate is 500 nm to 500 μm.

[0013] Preferably, the flow rate of nitrogen is 30-80 sccm (standard cubic centimeter per minute) during the nitrogen passing process.

[0014] Preferably, the chemical vapor deposition is carried out at a temperature of 550-700 ℃, and the deposition time is 20-60 min.

[0015] The application further provides the van der Waals tellurium nanomaterial prepared by the above preparation method, wherein the van der Waals tellurium nanomaterial is in a rod-like structure, i.e. the van der Waals tellurium nanomaterial is composed of van der Waals tellurium nanorods, the length of the van der Waals tellurium nanorod is 3.73-12.28 μm, and the thickness of the van der Waals tellurium nanomaterial is less than 200 nm.

[0016] The application further provides an application of the above van der Waals tellurium nanomaterial in a photoelectric device.

[0017] The application further provides a photoelectric device comprising the above van der Waals tellurium nanomaterial and metal electrodes at two ends of the van der Waals tellurium nanorod in the van der Waals tellurium nanomaterial.

[0018] The bulk photovoltaic effect of the photoelectric device has a very wide spectrum, covering the ultraviolet band of 390 nm to the medium wave infrared band of 3.8 μm; and the photoelectric device has a high current density of up to 70.4 A·cm -2 .

[0019] Preferably, the distance between the metal electrodes at the two ends of the van der Waals tellurium nanorod in the van der Waals tellurium nanomaterial is 2.5-14.5 μm;

[0020] The width of the van der Waals tellurium nanorod in the van der Waals tellurium nanomaterial is 0.2-7.8 μm.

[0021] Preferably, the material of the metal electrode is one or more of gold, platinum and palladium.

[0022] The application also provides a preparation method of the photoelectric device, comprising the following steps:

[0023] After coating photoresist on the substrate with the surface of van der Waals tellurium nanomaterial, selecting a van der Waals tellurium nanorod in the van der Waals tellurium nanomaterial, and sequentially performing electron beam lithography and development to expose the positions for preparing electrodes at the two ends of the selected van der Waals tellurium nanorod, evaporating electrodes, and removing the photoresist, the photoelectric device is obtained. BRIEF DESCRIPTION OF DRAWINGS

[0024] Fig. 1 is a microstructure diagram of the van der Waals tellurium nanomaterial prepared in Example 1;

[0025] Fig. 2 is a particle size distribution diagram of the van der Waals tellurium nanomaterial prepared in Example 1;

[0026] Fig. 3 is a structure schematic diagram of the photoelectric device in Example 1;

[0027] Fig. 4 is a current-voltage curve of the photoelectric device in Example 1 in a dark state;

[0028] Fig. 5 is a photoelectric current-time curve of the photoelectric device in Example 1;

[0029] Fig. 6 is a current-voltage curve of the photoelectric device in Example 1;

[0030] Fig. 7 is a micro-area scanning photoelectric characterization of the photoelectric device in Example 1 under a light source with a wavelength of 1.31 μm;

[0031] Fig. 8 is a micro-area scanning photoelectric characterization of the photoelectric device in Example 1 under a light source with a wavelength of 1.55 μm;

[0032] Fig. 9 is a relationship between the photoelectric current and the device channel position in the micro-area scanning photoelectric characterization of the photoelectric device in Example 1;

[0033] Fig. 10 is a wavelength spectrum line of the bulk photovoltaic response of the photoelectric device in Example 1;

[0034] Fig. 11 is a relationship between the 1.31 μm light power density and the bulk photovoltaic response current of the photoelectric device in Example 1;

[0035] Fig. 12 is a structural schematic diagram of the photoelectric device of Example 2;

[0036] Fig. 13 is a micro-area scanning photoelectric characterization of the photoelectric device of Example 2 under a light source with a wavelength of 830 nm;

[0037] Fig. 14 is a micro-area scanning photoelectric characterization of the photoelectric device of Example 2 under a light source with a wavelength of 1.31 μm;

[0038] Fig. 15 is a micro-area scanning photoelectric characterization of the photoelectric device of Example 2;

[0039] Fig. 16 is a graph of the photoelectric current versus time of the photoelectric device of Example 2 under irradiation of a light with a wavelength of 1.31 μm;

[0040] Fig. 17 is a graph of the photoelectric current versus time of the photoelectric device of Example 2 under irradiation of a light with a wavelength of 1.55 μm;

[0041] Fig. 18 is an atomic force microscope characterization of the van der Waals tellurium nanomaterial of Example 1. DETAILED DESCRIPTION

[0042] The present application provides a preparation method of a van der Waals tellurium nanomaterial, comprising the following steps:

[0043] The van der Waals tellurium nanomaterial is obtained by chemical vapor deposition on the surface of a substrate using tin telluride as a raw material.

[0044] The chemical vapor deposition is performed under a nitrogen atmosphere.

[0045] In the present application, all the raw materials are commercially available products well known to those skilled in the art, unless otherwise specified.

[0046] In the present application, the van der Waals tellurium nanomaterial refers to a tellurium nanomaterial in which tellurium atoms form helical chains and adjacent helical chains are combined by van der Waals force.

[0047] In the present application, the substrate preferably comprises a silicon substrate, a glass substrate, a mica substrate or a sapphire substrate, and more preferably a silicon substrate; the thickness of the substrate is preferably 500 nm to 500 μm, more preferably 500 nm to 100 μm, and most preferably 500 nm to 10 μm.

[0048] In the present application, the substrate is preferably placed downstream of a quartz tube, and the tin telluride is preferably placed in a ceramic boat at the center of the quartz tube.

[0049] Before the chemical vapor deposition, the present application preferably carries out air exhaust. The present application does not have any special limitation on the air exhaust, which can be operated by methods well known to those skilled in the art and can ensure that the ambient pressure is reduced to below 10 Pa.

[0050] In the present application, the flow rate of nitrogen during the nitrogen feeding is preferably 30-80 sccm, more preferably 40-60 sccm, and most preferably 50 sccm.

[0051] In the present application, the chemical vapor deposition is preferably carried out at a temperature of 550-700℃, more preferably at a temperature of 580-680℃, and most preferably at a temperature of 600-650℃; the deposition time of the chemical vapor deposition is preferably 20-60 min, more preferably 30-50 min, and most preferably 30-40 min.

[0052] After the chemical vapor deposition, the present application also preferably comprises cooling, which does not have any special limitation and can be cooled by methods well known to those skilled in the art.

[0053] The present application also provides a van der Waals tellurium nanomaterial prepared by the above preparation method, which is in a rod-like structure, i.e., the van der Waals tellurium nanomaterial is composed of van der Waals tellurium nanorods, the length of the van der Waals tellurium nanorods is 3.73-12.28 μm, and the thickness of the van der Waals tellurium nanomaterial is less than 200 nm.

[0054] The present application also provides an application of the above van der Waals tellurium nanomaterial in photoelectric devices.

[0055] The present application also provides a photoelectric device comprising the van der Waals tellurium nanomaterial and metal electrodes at both ends of the van der Waals tellurium nanorods in the van der Waals tellurium nanomaterial.

[0056] In the present application, the distance between the metal electrodes at both ends of the van der Waals tellurium nanorods in the van der Waals tellurium nanomaterial is preferably 2.5-14.5 μm, and more preferably 3.7-6.8 μm; the width of the van der Waals tellurium nanorods in the van der Waals tellurium nanomaterial is preferably 0.2-7.8 μm, and more preferably 0.32-2 μm.

[0057] In the present application, the material of the metal electrodes is preferably one or more of gold, platinum and palladium, and more preferably gold. In the present application, the thickness of the metal electrodes is preferably 80-200 nm, more preferably 90-120 nm, and most preferably 100 nm.

[0058] The present application also provides a preparation method of the photoelectric device, which comprises the following steps:

[0059] After coating photoresist on the substrate with van der Waals tellurium nanomaterials, a van der Waals tellurium nanorod is selected from the van der Waals tellurium nanomaterials, and electron beam lithography and development are sequentially performed to expose the positions for preparing electrodes at two ends of the selected van der Waals tellurium nanorod, then the electrodes are evaporated, and the photoresist is removed to obtain the photoelectric device.

[0060] In the present application, the preparation method of the substrate with van der Waals tellurium nanomaterials is preferably transferring the van der Waals tellurium nanomaterials prepared on the surface of a substrate by the preparation method of the van der Waals tellurium nanomaterials to the surface of a SiO2 / Si substrate. The SiO2 / Si substrate preferably comprises a silicon substrate and a silicon dioxide layer on the surface of the silicon substrate. The van der Waals tellurium nanomaterials are preferably transferred to the surface of the silicon dioxide layer. The present application does not have any special limitation on the method used for the transferring, which can be performed by using a method well known to those skilled in the art.

[0061] In the present application, the photoresist is preferably a polymethyl methacrylate (PMMA) photoresist, and the thickness of the photoresist is preferably 300-700 nm, more preferably 500 nm. The present application does not have any special limitation on the coating, which can be performed by using a method well known to those skilled in the art.

[0062] In the present application, the selected van der Waals tellurium nanorod is preferably selected by using a microscope. The length of the selected van der Waals tellurium nanorod is preferably 3.73-12.28 μm.

[0063] The present application does not have any special limitation on the electron beam lithography and development, which can be performed by using a method well known to those skilled in the art.

[0064] In the present application, the thickness of the metal electrode is preferably 80-200 nm, more preferably 90-120 nm, and most preferably 100 nm. The present application does not have any special limitation on the evaporation, which can be performed by using a method well known to those skilled in the art.

[0065] In the present application, the removal of the photoresist is preferably soaking the electrode after evaporation in an acetone solution, and the soaking time is preferably 3-15 min, more preferably 3-8 min, and most preferably 5 min.

[0066] The van der Waals tellurium nanomaterials with wide-spectrum bulk photovoltaic response, the preparation method and application thereof, the photoelectric device and the preparation method thereof provided by the present application will be described in detail below with reference to the examples, but they should not be understood as limiting the scope of protection of the present application.

[0067] Example 1

[0068] Put tin telluride as raw material in the center of the quartz tube ceramic boat, 500 nm thick silicon substrate is placed downstream of the quartz tube, then the air in the quartz tube is discharged, the pressure of the quartz tube is reduced to below 10 Pa, then nitrogen is introduced at a flow rate of 50 sccm, heated to 650 DEG C and kept for 30 min, after natural cooling, the van der waals tellurium nanomaterial on the surface of the Si substrate is obtained;

[0069] The van der waals tellurium nanomaterial on the surface of the Si substrate is transferred to a silicon substrate with a 280 nm thick silicon dioxide layer on the surface, then a layer of PMMA photoresist with a thickness of 500 nm is brushed, a van der waals tellurium nanorod with a length of 9.68 μm is found under a microscope, the position of the evaporation electrode (located at both ends of the van der waals tellurium nanorod) is exposed after electron beam lithography and development, a 100 nm thick gold electrode is evaporated by thermal evaporation to make the gold electrode overlap at both ends of the van der waals tellurium nanorod, and then the PMMA glue is removed after soaking in acetone solution for 5 min, to obtain a photoelectric device (structure as shown in Figure 3, the channel length (distance between the two gold electrodes) of the photoelectric device is 6.1 μm, and the width (width of the van der waals tellurium nanorod) is 2.8 μm);

[0070] The van der waals tellurium nanomaterial is subjected to microscope test, and the test results are shown in Figures 1-2, wherein Figure 1 is a microstructure diagram of the van der waals tellurium nanomaterial, and Figure 2 is a length distribution diagram of the van der waals tellurium nanorod in the van der waals tellurium nanomaterial, as shown in Figures 1-2, the van der waals tellurium nanomaterial is a rod structure, that is, the van der waals tellurium nanomaterial is composed of van der waals tellurium nanorods, the length of the van der waals tellurium nanorod is 3.73-12.28 μm, and the average length is 5.19 μm;

[0071] The van der waals tellurium nanomaterial is subjected to atomic force microscope characterization, and the test results are shown in Figure 18, as shown in Figure 18, the thickness of the van der waals tellurium nanomaterial is 198.2 nm.

[0072] The dark state current-voltage curve of the photoelectric device is tested, and the test results are shown in Figure 4, as shown in Figure 4, the current-voltage characteristics of the photoelectric device show that a good ohmic contact is formed between gold and tellurium.

[0073] The photoelectric device is subjected to photoelectric characterization, and the voltage applied to the two electrodes of the photoelectric device is zero volt. First, the photocurrent and time test is carried out, and the test results are shown in Figures 5-6, wherein Figure 5 is a photocurrent-time curve of the photoelectric device, and Figure 6 is a current-voltage curve of the photoelectric device. As shown in Figures 5-6, under 1.31 μm light, a stable photocurrent can be quickly generated, and the generated photocurrent is as high as dozens of microamperes, when the light power changes from 157 mW / mm 2 to 3.5 mW / mm2 The photocurrent gradually decreases as the micro-irradiation moves away from the metal electrode. As can be seen from Fig. 6, under dark condition, the current-voltage curve of the van der Waals tellurium photovoltaic device passes through the origin. As the power density of the incident light increases, the short-circuit current and open-circuit voltage increase simultaneously and deviate from the origin. This non-zero characteristic can be attributed to the photovoltaic effect, but the linear characteristic of the photovoltaic device is quite different from the exponential curve (I = I0[exp(qV / kT)-1], an e exponential relationship) observed in p-n junction devices.

[0074] The photovoltaic device was subjected to micro-irradiation photoelectric characterization, and the voltage applied to the electrodes on both ends of the photovoltaic device was zero volts. The test light source wavelengths were 1.31 μm and 1.55 μm, and the power densities were 1.64 and 0.65 mW / mm2, respectively. 2 Fig. 7 is a micro-irradiation photoelectric characterization diagram of the photovoltaic device under a light source with a wavelength of 1.31 μm, and Fig. 8 is a micro-irradiation photoelectric characterization diagram of the photovoltaic device under a light source with a wavelength of 1.55 μm. As can be seen from Figs. 7-8, a larger photocurrent is observed in the channel of the photovoltaic device, rather than in the region of the electrode and the tellurium nanomaterial contact interface.

[0075] Fig. 9 is a diagram of the photocurrent and the position of the device channel of the micro-irradiation photoelectric characterization of the photovoltaic device. As can be seen from Fig. 9, when the micro-irradiation infrared light moves away from the metal electrode, the photocurrent gradually increases, and almost reaches a maximum in the middle of the channel of the photovoltaic device. When the micro-irradiation infrared light approaches the other end of the metal electrode, the photocurrent gradually decreases. The micro-irradiation photoelectric characterization results rule out other photoelectric effects, and the photovoltaic device has a bulk photovoltaic effect.

[0076] The photovoltaic device was subjected to Fourier photocurrent characterization, and the voltage applied to the electrodes on both ends of the photovoltaic device was zero volts. The characterization results are shown in Figs. 10-11, wherein Fig. 10 is a bulk photovoltaic response wavelength spectrum of the photovoltaic device, and Fig. 11 is a diagram of the 1.31 μm light power density and the bulk photovoltaic response current of the photovoltaic device. As can be seen from Fig. 10, the photovoltaic device has a very wide bulk photovoltaic response band, covering the ultraviolet band of 390 nm to the mid-infrared band of 3.8 μm. Compared with the reported semiconductors (MoS2, WS2, PZTO lead zirconate titanate, OMPH (perovskite organic metal halide), MPI (MAPbI3), KBNNO ([KNbO3]1-x[BaNi 1 / 2 Nb 1 / 2 O3-δ] xCompared to the ultraviolet and visible light spectral ranges observed in BFO (BiFeO3), BFCO (Bi2FeCrO6), and BTO (barium titanate), the bulk photovoltaic response band of the aforementioned optoelectronic device is significantly broadened. As shown in Figure 11, the bulk photovoltaic effect of the aforementioned optoelectronic device exhibits a high current density of 70.4 A·cm⁻¹ in the communication band at 1.3 μm. -2 Within the infrared communication band, the bulk photovoltaic response photocurrent density of the optoelectronic device is not only comparable to the photocurrent density of current ultraviolet and visible light materials, but also exceeds the photocurrent generated by mid-wave infrared half-metals.

[0077] Example 2

[0078] Tin telluride was placed in a ceramic boat in the center of a quartz tube as a raw material. A 500 nm thick silicon substrate was placed downstream of the quartz tube. Then, the air in the quartz tube was purged until the pressure in the quartz tube dropped below 10 Pa. Nitrogen gas was then introduced at a flow rate of 50 sccm. The temperature was heated to 650 °C and held for 30 min. After natural cooling, van der Waals telluride nanomaterials were obtained on the surface of the Si substrate.

[0079] The van der Waals tellurium nanomaterials on the surface of the Si substrate were transferred to a silicon substrate with a silicon dioxide layer of 280 nm thickness. Then, a PMMA photoresist layer of 500 nm thickness was applied. Under a microscope, van der Waals tellurium nanorods with a length of 11.68 μm were found. The positions of the vapor-deposited electrodes (located at both ends of the van der Waals tellurium nanorods) were exposed through electron beam lithography and development. Gold electrodes with a thickness of 100 nm were deposited by thermal evaporation and attached to both ends of the van der Waals tellurium nanorods. After immersion in acetone solution for 5 min, the PMMA photoresist was removed, and an optoelectronic device was obtained (the structure is shown in Figure 12, the channel length (distance between the two gold electrodes) of the optoelectronic device is 3.8 μm, and the width (width of the van der Waals tellurium nanorods) is 0.23 μm).

[0080] The optoelectronic device was characterized by micro-area scanning photoelectric characteristics. The voltage applied to the electrodes at both ends of the optoelectronic device was zero volts. The test light source wavelengths were 830 nm and 1.31 μm, and the power densities were 0.12 mW / mm², respectively. 2 and 0.04mW / mm 2 Figure 13 shows the micro-area scanning photoelectric characterization of the optoelectronic device at a light source with a wavelength of 830 nm, and Figure 14 shows the micro-area scanning photoelectric characterization of the optoelectronic device at a light source with a wavelength of 1.31 μm. As can be seen from Figures 13 and 14, a large photocurrent is observed in the channel of the optoelectronic device, rather than in the interface region between the electrode and the tellurium nanomaterial.

[0081] Figure 15 is a plot of micro-scan photoelectric characterization of the photoelectric current versus the position of the channel of the photoelectric device. As can be seen from Figure 15, when the micro-infrared light moves from one end of the metal electrode and away from the metal electrode, the photoelectric current gradually increases and almost reaches the maximum in the middle of the channel of the photoelectric device. When the micro-infrared light approaches the other end of the metal electrode, the photoelectric current gradually decreases. The micro-scan photoelectric characterization result shows that the length of the channel is 3.8 μm and the width is 0.23 μm. The van der Waals tellurium nanorod also has a bulk photovoltaic effect.

[0082] The photoelectric device was subjected to Fourier photoelectric current characterization, and the voltage applied to the electrodes at both ends of the photoelectric device was zero volt. The characterization results are shown in Figures 16-17, in which Figure 16 is a plot of the photoelectric current versus time under the irradiation of light at 1.31 μm, and Figure 17 is a plot of the photoelectric current versus time under the irradiation of light at 1.55 μm. As can be seen from Figures 16-17, under the irradiation of light at 1.31 μm and 1.55 μm, the light power was changed from 17 mW / mm 2 to 125 mW / mm 2 and from 35.1 mW / mm 2 to 99.5 mW / mm 2 , the device could quickly generate stable photoelectric current, and the generated photoelectric current was as high as several hundred nanoamperes.

[0083] The above description is only preferred embodiments of the present application, and it should be noted that for those skilled in the art, without departing from the principles of the present application, a number of improvements and refinements can be made, and these improvements and refinements should also be considered as the protection scope of the present application.

Claims

1. Use of a van der Waals tellurium nanomaterial in an optoelectronic device, characterized in that, The preparation method of the van der Waals tellurium nanomaterial comprises the following steps: The van der Waals tellurium nanomaterial is obtained by chemical vapor deposition on the surface of a substrate with tin telluride as raw material; The chemical vapor deposition is carried out under the condition of nitrogen flow; The flow rate of nitrogen is 30-80 sccm during the nitrogen flow process; The van der Waals tellurium nanomaterial is in a rod-like structure; The chemical vapor deposition is carried out at a temperature of 650 DEG C and a deposition time of 30 min. The substrate comprises at least one of a silicon substrate, a glass substrate, a mica substrate and a sapphire substrate; 2. Use according to claim 1, wherein The thickness of the substrate is 500 nm-500 mu m. The length of the van der Waals tellurium nanorod in the van der Waals tellurium nanomaterial is 3.73-12.28 mu m, and the thickness of the van der Waals tellurium nanomaterial is less than 200 nm.

3. Use according to claim 1 or 2, characterized in that, The van der Waals tellurium nanomaterial and the metal electrodes at both ends of the van der Waals tellurium nanorod in the van der Waals tellurium nanomaterial are included; 4. An optoelectronic device, characterized by The preparation method of the van der Waals tellurium nanomaterial comprises the following steps: The van der Waals tellurium nanomaterial is obtained by chemical vapor deposition on the surface of a substrate with tin telluride as raw material; The chemical vapor deposition is carried out under the condition of nitrogen flow; The flow rate of nitrogen is 30-80 sccm during the nitrogen flow process; The van der Waals tellurium nanomaterial is in a rod-like structure; The chemical vapor deposition is carried out at a temperature of 650 DEG C and a deposition time of 30 min. The distance between the metal electrodes at both ends of the van der Waals tellurium nanorod in the van der Waals tellurium nanomaterial is 2.5-14.5 mu m; 5. The optoelectronic device of claim 4, wherein, The width of the van der Waals tellurium nanorod in the van der Waals tellurium nanomaterial is 0.2-7.8 mu m. The material of the metal electrode is one or more of gold, platinum and palladium.

6. The optoelectronic device of claim 4, wherein, The method comprises the following steps:

7. A method of producing an optoelectronic device according to any one of claims 4 to 6, characterised in that, After a photoresist is coated on the substrate with the surface being the van der Waals tellurium nanomaterial, a van der Waals tellurium nanorod is selected in the van der Waals tellurium nanomaterial, electron beam lithography and development are sequentially carried out until the positions for preparing electrodes are exposed at both ends of the selected van der Waals tellurium nanorod, electrodes are evaporated, the photoresist is removed, and the optoelectronic device is obtained. ​

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