Nanosheet electrolyte light emitting transistor

Abstract

The invention discloses a nanosheet electrolyte light-emitting transistor, which comprises an insulating layer; the gate electrode is arranged on one surface of the insulating layer; the n-type semiconductor layer is arranged on the other surface, opposite to the gate electrode, of the insulating layer; the source electrode is arranged on a part of the surface of the n-type semiconductor; the nanosheet electrolyte light-emitting layer is arranged on the surface of the other part of the n-type semiconductor; the nanosheet electrolyte light-emitting layer comprises a heterostructure nanosheet and an electrolyte; the hole transport layer is arranged on the nanosheet electrolyte light-emitting layer; a hole injection layer disposed on the hole transport layer; and the drain electrode is arranged on the hole injection layer. According to the invention, the nanosheet electrolyte light-emitting layer can form a double-electrode layer at an electrode interface through anions and cations under the action of an electric field, so that the injection and transmission of charges are improved.

Description

Technical Field

[0001] This invention relates to the technical field of light-emitting transistors, and particularly to a nanosheet electrolyte light-emitting transistor. Background Technology

[0002] Nanosheets, a novel type of semiconductor nanoparticle with a diameter approaching the exciton Bohr radius, possess a unique "quantum confinement effect" that enables tunable wavelengths. In recent years, due to their excellent optoelectronic properties (high color purity, high quantum yield, etc.), solution-processability, and high stability, nanosheets have been widely used in various fields such as lasers, detectors, solar cells, and light-emitting diodes (LEDs). With the application of nanosheets in the field of light-emitting displays, they have demonstrated outstanding performance in electroluminescence (EL), becoming a highly anticipated field.

[0003] For nanosheet EL devices, electron leakage caused by unbalanced charge injection and transport remains the core problem restricting device efficiency and stability; an unreasonable device structure can cause a sharp increase in leakage current, leading to an increase in the probability of nonradiative recombination of electrons and holes, and more severe electron leakage and exciton quenching. Summary of the Invention

[0004] In order to overcome the above-mentioned shortcomings and deficiencies of the prior art, the present invention aims to provide a nanosheet electrolyte light-emitting transistor to solve the problem of electron leakage caused by unbalanced charge injection and transport in traditional light-emitting transistors.

[0005] The objective of this invention is achieved through the following technical solution: Embodiments of the present invention provide a nanosheet electrolyte light-emitting transistor, comprising: Insulating layer; The gate electrode is disposed on one of the surfaces of the insulating layer; An n-type semiconductor layer is disposed on the other surface of the insulating layer opposite to the gate electrode; The source electrode is disposed on a portion of the surface of the n-type semiconductor; A nanosheet electrolyte light-emitting layer is disposed on another portion of the surface of the n-type semiconductor; the nanosheet electrolyte light-emitting layer comprises a heterostructured nanosheet and an electrolyte; the heterostructured nanosheet is a two-dimensional composite structure formed by interfacial coupling of two or more different semiconductor materials; A hole transport layer is disposed on the nanosheet electrolyte luminescent layer; A hole injection layer is disposed on the hole transport layer; The drain electrode is disposed on the hole injection layer.

[0006] In some embodiments of the present invention, the nanosheet electrolyte luminescent layer is formed by coating a nanosheet electrolyte solution; the nanosheet electrolyte solution is obtained by mixing (CdSe / CdS)@(CdS / CdZnS) nanosheet stock solution with an electrolyte.

[0007] In some embodiments of the present invention, the electrolyte is THA-BF4, Li-TFSI, [CH3(CH2)3]4NCl, [CH3(CH2)3]4NBr, C 14 H 32 Any of BrP (tributylethylphosphine bromide).

[0008] Embodiments of the present invention also provide a method for fabricating a nanosheet electrolyte light-emitting transistor, comprising the following steps: A substrate is provided, the substrate including a gate electrode and an insulating layer; An n-type semiconductor is fabricated on the substrate, the n-type semiconductor covering the surface of the insulating layer; A source electrode is fabricated on a portion of the surface of the n-type semiconductor; A nanosheet electrolyte solution is spin-coated onto another portion of the surface of the n-type semiconductor to obtain a nanosheet electrolyte light-emitting layer; the nanosheet electrolyte solution is obtained by mixing a heterostructure nanosheet solution with an electrolyte; the heterojunction nanosheet is a two-dimensional composite structure formed by interfacial coupling of two or more different semiconductor materials. A hole transport layer is prepared on the nanosheet electrolyte light-emitting layer; A hole injection layer is prepared on the hole transport layer; A drain electrode is fabricated on the hole injection layer.

[0009] In some embodiments of the present invention, the heterojunction nanosheets are (CdSe / CdS)@(CdS / CdZnS) heterostructure nanosheets, which are prepared as follows: Based on a bare CdSe core, it is first passivated externally with a CdS crown; Monolayers of CdS were deposited on the top and bottom of the nanosheets, respectively, to serve as seeds for the final thermal injection growth. CdZnS shells are vertically grown at high temperatures.

[0010] In some embodiments of the present invention, the preparation process of the nanosheet electrolyte solution includes the following steps: The nanosheet stock solution is washed to obtain a nanosheet solution, wherein the nanosheet stock solution includes n-hexane and nanosheets dispersed in n-hexane; The nanosheet solution is added to the electrolyte solution and stirred to obtain the nanosheet electrolyte solution.

[0011] In some embodiments of the present invention, the nanosheet stock solution is prepared as follows: A mixed solution is formed by mixing oleylamine-coated (CdSe / CdS)@(CdS) nanosheets, 1-octadecene, oleic acid, zinc acetate, and cadmium acetate. Degas the mixed solution; Add oleylamine to the degassed mixed solution; Heating the mixed solution; After the temperature of the mixed solution reaches a first preset temperature, a zinc mercaptan-1-octadecene anion precursor is added to the mixed solution at a first injection rate. After the temperature of the mixed solution reaches the second preset temperature, zinc mercaptan-1-octadecene anion precursor is added to the mixed solution at a second injection rate; When the mixed solution reaches the reaction temperature, the mixed solution is kept at the reaction temperature for a preset reaction time, and then subjected to water bath quenching. The quenched mixture was diluted with n-hexane and then centrifuged to precipitate unstable particles. The supernatant in the mixed solution was mixed with ethanol, and then centrifuged again to obtain precipitated (CdSe / CdS)@(CdS / CdZnS) heterostructure nanosheets. The precipitated (CdSe / CdS)@(CdS / CdZnS) heterostructured nanosheets were dispersed in n-hexane to obtain the nanosheet stock solution.

[0012] In some embodiments of the present invention, the first preset temperature is 160~170℃, and the second preset temperature is 235~245℃.

[0013] In some embodiments of the present invention, the first injection rate is 8~12 ml / h; the first injection rate is 3~5 ml / h.

[0014] In some embodiments of the present invention, the process of cleaning the nanosheet stock solution includes the following steps: Ethanol was added to the nanosheet stock solution to produce a precipitate; The nanosheet stock solution after precipitation is placed in a centrifuge for centrifugation until the supernatant is clear. Pour off the supernatant and add n-octane, then let stand until the precipitate is completely dissolved. Ethyl acetate is added to a solution containing n-octane to produce a precipitate; The solution after precipitation is placed in a centrifuge and centrifuged until the supernatant is clear. Pour off the supernatant and add chlorobenzene or cyclohexanone reagent to fully dissolve the precipitate; The solution after adding chlorobenzene or cyclohexanone reagent is diluted to obtain a nanosheet solution.

[0015] The heterojunction nanosheets of this invention are two-dimensional composite structures formed by interfacial coupling of two or more different semiconductor materials. Their core characteristics and similarities lie in the differences in band structure and the synergistic effect of the interfacial electric field. (CdSe / CdS)@(CdS / CdZnS) is a complex core / crown / shell / shell multilayer heterojunction nanosheet, and this complex structure is applicable to this patent; therefore, simpler heterojunction nanosheets such as core / crown and core / shell structures are also applicable. The heterojunction nanosheets of this invention have the following characteristics: Common structural features: Both are formed through interfacial coupling of two different semiconductor materials, with charge separation driven by differences in band structure. Functional advantages: The two-dimensional properties of nanosheets (such as high specific surface area) and the built-in electric field of heterojunctions work together to improve photocatalysis and photoelectric conversion efficiency.

[0016] Type association: heterojunction (such as type II) nanosheets, the charge transfer mode can be further modulated to control the carrier distribution.

[0017] The electrolyte of this invention is a weakly polar ionic solution soluble in toluene or chlorobenzene solvents. Examples include THA-BF4, Li-TFSI, [CH3(CH2)3]4NCl, [CH3(CH2)3]4NBr, and C. 14 H 32 For ionic liquids such as BrP (tributylethylphosphine bromide), if the ions are not only predominantly methyl-linked but also have relatively weak polarity between the cations and anions, then this type of ionic liquid can be used in this system. The predominance of the methyl chain allows the ionic liquid to dissolve well in toluene or chlorobenzene solvents, while the relatively weak polarity does not affect the stability of the luminescent material.

[0018] Compared with existing technologies, the nanosheet electrolyte light-emitting transistor and its fabrication method provided in this application have the following advantages and beneficial effects: By incorporating the nanosheet electrolyte light-emitting layer of this invention, when the nanosheet electrolyte light-emitting transistor is in operation, the nanosheet electrolyte light-emitting layer forms an electric double layer at the electrode interface through cations and anions under the influence of an electric field, thereby improving charge injection and transport. This solves the problem of electron leakage caused by unbalanced charge injection and transport in traditional light-emitting transistors. Therefore, with the improvement in charge injection and transport by cations and anions, the light emission of the nanosheet electrolyte light-emitting transistor in this application will be more uniform and brighter. Attached Figure Description

[0019] Figure 1A schematic flowchart illustrating a method for fabricating a nanosheet electrolyte light-emitting transistor according to one embodiment of this application; Figure 2 A schematic diagram of the structure of a nanosheet electrolyte light-emitting transistor provided in another embodiment of this application; Figure 3 This is a schematic diagram of the structure of an existing nanosheet light-emitting transistor; Figure 4 for Figure 2 NE-LET devices and Figure 3 The transfer characteristic curve of the N-LET device in the diagram; Figure 5 for Figure 3 Output characteristic curves of N-LET devices in the diagram; Figure 6 for Figure 2 Output characteristic curves of NE-LET devices in the diagram; Figure 7 for Figure 3 Optical photographs of N-LET devices at different gate voltages; Figure 8 for Figure 2 Optical photographs of the NE-LET device at different gate voltages. Detailed Implementation

[0020] The present invention will be further described in detail below with reference to the embodiments, but the implementation of the present invention is not limited thereto.

[0021] Please see Figure 1 One embodiment of this application provides a method for fabricating a nanosheet electrolyte light-emitting transistor, comprising the following steps: A substrate is provided, the substrate including a gate electrode and an insulating layer.

[0022] An n-type semiconductor is fabricated on the substrate, and the n-type semiconductor covers the surface of the insulating layer. Specifically, before fabricating the n-type semiconductor on the substrate, the Si / SiO2 substrate is cleaned sequentially with acetone, water, and ethanol, and then dried with a nitrogen gun.

[0023] A source electrode is fabricated on a portion of the surface of the n-type semiconductor. Specifically, the source electrode is fabricated on a portion of the surface of the n-type semiconductor using a thermal evaporation process. The source electrode is an aluminum electrode with a thickness of 120 nm.

[0024] A nanosheet electrolyte solution is spin-coated onto another portion of the surface of the n-type semiconductor to obtain a nanosheet electrolyte light-emitting layer. In this embodiment, the thickness of the nanosheet electrolyte light-emitting layer is between 20 and 30 nm.

[0025] A hole transport layer was prepared on the nanosheet electrolyte luminescent layer. In this embodiment, the hole transport layer was prepared on the nanosheet electrolyte luminescent layer using a thermal evaporation process. The material used to prepare the hole transport layer was CBP (4,4'-Bis(carbazol-9-yl)biphenyl, 4,4'-bis(9-carbazole)biphenyl). The thickness of the hole transport layer was approximately 60 nm.

[0026] A hole injection layer is fabricated on the hole transport layer. Specifically, a MoO3 hole injection layer is fabricated on the hole transport layer using a thermal evaporation process. The thickness of the MoO3 hole injection layer is approximately 6 nm.

[0027] A drain electrode is fabricated on the hole injection layer. Specifically, the drain electrode is fabricated on the hole injection layer using a thermal evaporation process. The drain electrode is a gold electrode. The thickness of the drain electrode is approximately 10 nm.

[0028] In the fabrication method of the nanosheet electrolyte light-emitting transistor provided in the above embodiments, a nanosheet electrolyte solution is spin-coated onto another portion of the surface of the n-type semiconductor to obtain a nanosheet electrolyte light-emitting layer. When the nanosheet electrolyte light-emitting transistor is working, the nanosheet electrolyte light-emitting layer forms an electric double layer at the electrode interface through cations and anions under the action of an electric field, thereby improving charge injection and transport, thus solving the problem of electron leakage caused by unbalanced charge injection and transport in traditional light-emitting transistors. Therefore, with the improvement of charge injection and transport by cations and anions, the light emission of the nanosheet electrolyte light-emitting transistor in this application will be more uniform and brighter.

[0029] In fact, during the operation of a conventional nanosheet light-emitting transistor, electrons are injected from the gate electrode and transported along the direction of the transistor channel. A large number of electrons are injected into the nanosheet layer along the region near the electrode channel, where they recombine with holes to achieve light emission. The electron transport path is as follows... Figure 3 As shown by dashed arrows ① and ② in the diagram. The time required for electrons to travel along the direction of dashed arrow ② is relatively long, and the energy levels of indium oxide and the nanosheet are mismatched. Therefore, it is difficult for electrons to be injected into the center of the luminescent region and into the region far from the electrode channel, resulting in uneven electron injection throughout the luminescent region. Consequently, the luminescent region is mainly concentrated on the side closest to the electrode channel.

[0030] In the fabrication method of the nanosheet electrolyte light-emitting transistor provided in this application, a nanosheet electrolyte solution is spin-coated onto another portion of the surface of an n-type semiconductor to obtain a nanosheet electrolyte light-emitting layer. The cations and anions in the nanosheet electrolyte light-emitting layer can improve charge injection and transport. As the gate voltage increases, electrons away from the electrode channel are injected from indium oxide into the nanosheet electrolyte light-emitting layer, recombine with holes in the layer, and emit light. Therefore, with the improvement in charge injection and transport by cations and anions, the nanosheet light-emitting transistor fabricated in this application exhibits more uniform and brighter light emission.

[0031] In this embodiment, the gate electrode is made of heavily doped Si. The insulating layer is a SiO2 insulating layer. The n-type semiconductor is made of In2O3 or ZnO. The source electrode is made of Al. The nanosheets in the nanosheet electrolyte luminescent layer are (CdSe / CdS)@(CdS / CdZnS) heterostructure nanosheets. The electrolyte in the nanosheet electrolyte luminescent layer is THA-BF4 or Li-TFSI. The hole transport layer is made of CBP. The hole injection layer is made of MoO3. The drain electrode 8 is made of Au.

[0032] In one embodiment, the preparation process of the nanosheet electrolyte solution includes the following steps: The nanosheet stock solution is washed to obtain a nanosheet solution, wherein the nanosheet stock solution includes n-hexane and nanosheets dispersed in n-hexane; The nanosheet solution is added to the electrolyte solution and stirred to obtain the nanosheet electrolyte solution.

[0033] Specifically, the electrolyte solution can be THA-BF4 or Li-TFSI. In the specific operation, approximately 0.64 mg of THA-BF4 electrolyte liquid is weighed using a balance in a glove box (nitrogen environment), placed in a clean glass bottle, and 1 mL of nanosheet solution is added, wherein the mass ratio of nanosheets to THA-BF4 is 47:3. The solution is then stirred at room temperature for 30 min to obtain the nanosheet electrolyte liquid.

[0034] In one embodiment, the nanosheet solution is obtained through a nanosheet stock solution washing step, wherein the solution is chlorobenzene. The washing process of the nanosheet stock solution includes the following steps: Provide the nanosheet stock solution; Ethanol was added to the nanosheet stock solution to produce a precipitate; The nanosheet stock solution after precipitation is placed in a centrifuge for centrifugation until the supernatant is clear. Pour off the supernatant and add n-octane, then let stand until the precipitate is completely dissolved. Ethyl acetate is added to a solution containing n-octane to produce a precipitate; The solution after precipitation is placed in a centrifuge and centrifuged until the supernatant is clear. Pour off the supernatant and add chlorobenzene reagent to fully dissolve the precipitate; The solution after adding chlorobenzene reagent was diluted to obtain a nanosheet solution.

[0035] Specifically, in a glove box, add an appropriate amount of nanosheet stock solution (500 μL) to two clean glass reagent bottles (4 mL each). Add 3 mL of ethanol (HPLC grade / ultra-dry) to each bottle, causing precipitation. After capping, remove the bottles from the glove box and place them in a centrifuge at 3000 rpm for 3 min. If the supernatant is not clear, centrifuge again. Return the glass reagent bottles to the glove box, pour out the supernatant, and add 500 μL of n-octane (HPLC grade) to each bottle, allowing them to stand until the precipitate completely dissolves (approximately 1 h). Then add 3 mL of ethyl acetate (HPLC grade) to both solutions, causing precipitation. After capping, remove the glass reagent bottles from the glove box and place them in a centrifuge at 3000 rpm for 3 min. If the supernatant is not clear, centrifuge again. After complete centrifugation, return the glass reagent bottles to the glove box, pour out the supernatant, and add 500 μL of chlorobenzene reagent (HPLC grade) to each bottle, causing the precipitate to dissolve rapidly. After the precipitate has fully dissolved, the two solutions are combined, and the nanosheet solution is diluted with chlorobenzene solvent to 10 mg / mL to obtain the nanosheet solution. In another embodiment, cyclohexanone reagent can be used instead of chlorobenzene reagent.

[0036] In one embodiment, the preparation process of the nanosheet stock solution includes the following steps: A mixed solution is formed by mixing oleylamine-coated (CdSe / CdS)@(CdS) nanosheets, 1-octadecene, oleic acid, zinc acetate, and cadmium acetate. Degas the mixed solution; Add oleylamine to the degassed mixed solution; Heating the mixed solution; After the temperature of the mixed solution reaches a first preset temperature, a zinc mercaptan-1-octadecene anion precursor is added to the mixed solution at a first injection rate. After the temperature of the mixed solution reaches the second preset temperature, zinc mercaptan-1-octadecene anion precursor is added to the mixed solution at a second injection rate; When the mixed solution reaches the reaction temperature, the mixed solution is kept at the reaction temperature for a preset reaction time, and then subjected to water bath quenching. The quenched mixture was diluted with n-hexane and then centrifuged to precipitate unstable particles. The supernatant in the mixed solution was mixed with ethanol, and then centrifuged again to obtain precipitated (CdSe / CdS)@(CdS / CdZnS) heterostructure nanosheets. The precipitated (CdSe / CdS)@(CdS / CdZnS) heterostructured nanosheets were dispersed in n-hexane to obtain the nanosheet stock solution.

[0037] In one embodiment, the first preset temperature is 165°C and the first injection rate is 10 ml / h; the second preset temperature is 240°C and the first injection rate is 4 ml / h.

[0038] Specifically, (CdSe / CdS)@(CdS)((core / crown)@(shell)) nanosheets coated with oleylamine, 3.5 mL of 1-octadecene, 500 μL of oleic acid, 0.15 mmol of zinc acetate, and 0.05 mmol of cadmium acetate were mixed in a 50 mL three-necked flask. The mixture was degassed at room temperature for 1.5 h, and then further degassed at 80 °C for 30 min. The flask was then rinsed with argon, and 500 mL of oleylamine was added to the solution. The reaction temperature was set to 300 °C. After the temperature reached 165 °C, an anionic precursor of zinc thiol-1-octadecene (0.1 mol / L) was added to the solution at an injection rate of 10 mL / h. When the temperature reached above 240 °C, the injection rate was reduced to 4 mL / h. The flask was kept at 300 °C for 60–120 min, and then quenched in a water bath. The collected solution was diluted with 5 mL of n-hexane and centrifuged at 6000 rpm for 6 minutes to precipitate unstable particles. The supernatant was mixed with ethanol and then centrifuged again. The final precipitated nanosheets were dispersed in n-hexane for storage.

[0039] In one embodiment, the preparation process of the (CdSe / CdS)@(CdS / CdZnS) heterostructure nanosheets includes the following steps: Based on a bare CdSe core, it is first passivated externally with a CdS crown; Monolayers of CdS were deposited on the top and bottom of the nanosheets, respectively, to serve as seeds for the final thermal injection growth. CdZnS shells are vertically grown at high temperatures.

[0040] In this embodiment, the (CdSe / CdS)@(CdS / CdZnS) heterostructure nanosheet is a (core / crown)@(shell / shell) heterojunction structure.

[0041] Please see Figure 2 Another embodiment of this application provides a nanosheet electrolyte light-emitting transistor 100. The nanosheet electrolyte light-emitting transistor 100 is fabricated using the fabrication method of any of the above embodiments. The nanosheet electrolyte light-emitting transistor 100 includes a gate electrode 1, an insulating layer 2, an n-type semiconductor 3, a source electrode 4, a nanosheet electrolyte light-emitting layer 5, a hole transport layer 6, a hole injection layer 7, and a drain electrode 8.

[0042] The gate electrode 1 is disposed on one of the surfaces of the insulating layer 2.

[0043] The n-type semiconductor layer 3 is disposed on the other surface of the insulating layer 2 opposite to the gate electrode 1. Specifically, the gate electrode 1 and the n-type semiconductor layer 3 are disposed on two opposite surfaces of the insulating layer 2.

[0044] The source electrode 4 is disposed on a portion of the surface of the n-type semiconductor 3.

[0045] The nanosheet electrolyte light-emitting layer 5 is disposed on another part of the surface of the n-type semiconductor 3.

[0046] The hole transport layer 6 is disposed on the nanosheet electrolyte luminescent layer 5.

[0047] The hole injection layer 7 is disposed on the hole transport layer 6.

[0048] The drain electrode 8 is disposed on the hole injection layer 7.

[0049] The nanosheet electrolyte luminescent layer 5 is formed by spin-coating a nanosheet electrolyte solution. Annealing may be performed after spin-coating if necessary. The nanosheet electrolyte solution is obtained by miscibly dissolving a (CdSe / CdS)@(CdS / CdZnS) nanosheet stock solution with an electrolyte; the electrolyte is THA-BF4 or Li-TFSI.

[0050] In the nanosheet electrolyte light-emitting transistor 100 provided in the above embodiments, by providing the nanosheet electrolyte light-emitting layer 5, the injection and transport of anions and cations in the nanosheet electrolyte light-emitting layer 5 can be improved. As the gate voltage increases, electrons away from the electrode channel direction are injected from indium oxide into the nanosheet electrolyte light-emitting layer 5, and recombine with holes in the nanosheet electrolyte light-emitting layer 5 to emit light. Therefore, with the improvement of charge injection and transport by anions and cations, the light emission of the nanosheet electrolyte light-emitting transistor 100 is more uniform and brighter.

[0051] To illustrate the superior photoelectric properties of the nanosheet electrolyte light-emitting layer in this application, light-emitting transistor devices were fabricated using nanosheet solutions and nanosheet electrolyte solutions as light-emitting layer materials, respectively. For ease of description, in this embodiment, the light-emitting transistor device fabricated using nanosheet solutions as the light-emitting layer material is referred to as an N-LET device; the light-emitting transistor device fabricated using nanosheet electrolyte solutions as the light-emitting layer material is referred to as an NE-LET device.

[0052] The fabrication process of light-emitting transistors is as follows: (1) The Si / SiO2 substrate was cleaned with acetone, water and ethanol in sequence and then dried with a nitrogen gun.

[0053] (2) An n-type semiconductor is fabricated on a substrate using the ALD process, so that it covers part of the surface of the insulating layer; (3) A source electrode (aluminum electrode, 120 nm thick) is prepared on another part of the surface of the insulating layer by thermal evaporation. (4) Spin-coating a solution of light-emitting layer material nanosheets onto the surface of an n-type semiconductor to obtain a light-emitting layer (thickness of 20-30 nm). (5) A hole transport layer CBP (with a thickness of about 60 nm) was prepared on the light-emitting layer by thermal evaporation process. (6) A hole injection layer MoO3 (with a thickness of about 6 nm) was prepared on the hole transport layer by thermal evaporation process. (7) A drain electrode (gold electrode, approximately 10 nm) is prepared on the hole injection layer using a thermal evaporation process. The structure of the finally fabricated N-LET device is as follows Figure 3 As shown. The NE-LET device fabricated in this application is as follows: Figure 2 As shown.

[0054] The electrical performance of the constructed N-LET and NE-LET devices was tested using a semiconductor analyzer, when V DS When the voltage is 10V (i.e., 10V at the gold electrode and 0V at the aluminum electrode), V GS The transfer characteristic curves obtained from -50 V to 25 V are as follows: Figure 4 As shown, both N-LET and NE-LET devices can achieve an on / off ratio of 10. 7 The maximum turn-on current can reach over 1 mA. The transfer characteristic curves also show that the threshold voltage of the NE-LET device exhibits negative drift compared to the N-LET device; under the same gate voltage modulation, the NE-LET device generates a larger current, a phenomenon also evident in the output characteristic curves. From the current variation, the NE-LET device's light-emitting layer is more conducive to charge transport. The output characteristic curve of the N-LET device is shown below. Figure 5 As shown. The output characteristic curve of the NE-LET device is as follows. Figure 6 As shown. During the testing of the output characteristic curves of N-LET and NE-LET devices, the light-emitting characteristics of the devices under different gate voltage modulations were captured in real time. Optical images of the N-LET device under different gate voltages are shown below. Figure 7 As shown. Optical photographs of NE-LET devices at different gate voltages are shown in the figure. Figure 8 As shown in the optical photographs of the N-LET device at different gate voltages, it can be seen that when the gate voltage is less than -30 V, the entire device is in the off state, and the maximum current is only 3.2 × 10⁻⁶. -8 A. The device is not emitting light. When the gate voltage reaches -30 V, the N-LET device turns on, and the maximum current density is 8.2 × 10⁻⁶. - 5 A, at this point, light is emitted near the electrode channel side. As the gate voltage increases from -30 V to 10 V, the current density also increases from 3.2 × 10⁻⁶. -8 A rises to 1.9 x 10 -3 A. In N-LET devices, the light intensity gradually increases at the electrode channel, but most areas still fail to emit light. Looking at the light emission characteristics of N-LETs, the device does not turn on when the gate voltage is below -50 V, and the maximum current is only 5.8 × 10⁻⁶. -8 A. When the gate voltage reaches -40 V, the NE-LET device turns on, and the maximum current density is 1.4 × 10⁻⁶. -4 A. At this point, light is emitted near the electrode channel side, and the intensity of the light is clearly greater than that of N-LET, as can be seen from the optical photograph. As the gate voltage increases from -40V to 0V, the current density increases from 1.4 × 10⁻⁶. -4 A rises to 3.0 x 10 -3 In NE-LET devices, the light intensity gradually increases at the electrode channel until it covers the entire emitting area. Comparison of optical photographs clearly shows that NE-LET devices emit light more uniformly and brighter.

[0055] The above embodiments are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the embodiments described above. Any changes, modifications, substitutions, combinations, or simplifications made without departing from the spirit and principle of the present invention shall be considered equivalent substitutions and shall be included within the protection scope of the present invention.

Claims

1. A nanosheet electrolyte light-emitting transistor, characterized in that, include: Insulating layer; The gate electrode is disposed on one of the surfaces of the insulating layer; An n-type semiconductor layer is disposed on the other surface of the insulating layer opposite to the gate electrode; The source electrode is disposed on a portion of the surface of the n-type semiconductor; A nanosheet electrolyte light-emitting layer is disposed on another portion of the surface of the n-type semiconductor; the nanosheet electrolyte light-emitting layer comprises a heterostructured nanosheet and an electrolyte; the heterostructured nanosheet is a two-dimensional composite structure formed by interfacial coupling of two or more different semiconductor materials; A hole transport layer is disposed on the nanosheet electrolyte luminescent layer; A hole injection layer is disposed on the hole transport layer; The drain electrode is disposed on the hole injection layer.

2. The nanosheet electrolyte light-emitting transistor according to claim 1, characterized in that, The nanosheet electrolyte luminescent layer is formed by coating a nanosheet electrolyte solution; the nanosheet electrolyte solution is obtained by mixing (CdSe / CdS)@(CdS / CdZnS) nanosheet stock solution with an electrolyte.

3. The nanosheet electrolyte light-emitting transistor according to claim 1, characterized in that, The electrolyte is THA-BF4, Li-TFSI, [CH3(CH2)3]4NCl, [CH3(CH2)3]4NBr, C 14 H 32 Any of BrP (tributylethylphosphine bromide).

4. A method for fabricating a nanosheet electrolyte light-emitting transistor, characterized in that, Includes the following steps: A substrate is provided, the substrate including a gate electrode and an insulating layer; An n-type semiconductor is fabricated on the substrate, the n-type semiconductor covering the surface of the insulating layer; A source electrode is fabricated on a portion of the surface of the n-type semiconductor; A nanosheet electrolyte solution is spin-coated onto another portion of the surface of the n-type semiconductor to obtain a nanosheet electrolyte light-emitting layer; the nanosheet electrolyte solution is obtained by mixing a heterostructured nanosheet solution with an electrolyte. The heterojunction nanosheet is a two-dimensional composite structure formed by interfacial coupling of two or more different semiconductor materials. A hole transport layer is prepared on the nanosheet electrolyte light-emitting layer; A hole injection layer is prepared on the hole transport layer; A drain electrode is fabricated on the hole injection layer.

5. The method for fabricating a nanosheet electrolyte light-emitting transistor according to claim 4, characterized in that, The heterojunction nanosheets are (CdSe / CdS)@(CdS / CdZnS) heterostructure nanosheets, and their preparation is as follows: Based on a bare CdSe core, it is first passivated externally with a CdS crown; Monolayers of CdS were deposited on the top and bottom of the nanosheets, respectively, to serve as seeds for the final thermal injection growth. CdZnS shells are vertically grown at high temperatures.

6. The method for fabricating a nanosheet electrolyte light-emitting transistor according to claim 4, characterized in that, The preparation process of the nanosheet electrolyte solution includes the following steps: The nanosheet stock solution is washed to obtain a nanosheet solution, wherein the nanosheet stock solution includes n-hexane and nanosheets dispersed in n-hexane; The nanosheet solution is added to the electrolyte solution and stirred to obtain the nanosheet electrolyte solution.

7. The method for fabricating a nanosheet electrolyte light-emitting transistor according to claim 6, characterized in that, The nanosheet stock solution is prepared as follows: A mixed solution is formed by mixing oleylamine-coated (CdSe / CdS)@(CdS) nanosheets, 1-octadecene, oleic acid, zinc acetate, and cadmium acetate. Degas the mixed solution; Add oleylamine to the degassed mixed solution; Heating the mixed solution; After the temperature of the mixed solution reaches a first preset temperature, a zinc mercaptan-1-octadecene anion precursor is added to the mixed solution at a first injection rate. After the temperature of the mixed solution reaches the second preset temperature, zinc mercaptan-1-octadecene anion precursor is added to the mixed solution at a second injection rate; When the mixed solution reaches the reaction temperature, the mixed solution is kept at the reaction temperature for a preset reaction time, and then subjected to water bath quenching. The quenched mixture was diluted with n-hexane and then centrifuged to precipitate unstable particles. The supernatant in the mixed solution was mixed with ethanol, and then centrifuged again to obtain precipitated (CdSe / CdS)@(CdS / CdZnS) heterostructure nanosheets. The precipitated (CdSe / CdS)@(CdS / CdZnS) heterostructured nanosheets were dispersed in n-hexane to obtain the nanosheet stock solution.

8. The method for fabricating a nanosheet electrolyte light-emitting transistor according to claim 7, characterized in that, The first preset temperature is 160~170℃, and the second preset temperature is 235~245℃.

9. The method for fabricating a nanosheet electrolyte light-emitting transistor according to claim 7, characterized in that, The first injection rate is 8~12 ml / h; the first injection rate is 3~5 ml / h.

10. The method for fabricating a nanosheet electrolyte light-emitting transistor according to claim 6, characterized in that, The process of cleaning the nanosheet stock solution includes the following steps: Ethanol was added to the nanosheet stock solution to produce a precipitate; The nanosheet stock solution after precipitation is placed in a centrifuge for centrifugation until the supernatant is clear. Pour off the supernatant and add n-octane, then let stand until the precipitate is completely dissolved. Ethyl acetate is added to a solution containing n-octane to produce a precipitate; The solution after precipitation is placed in a centrifuge and centrifuged until the supernatant is clear. Pour off the supernatant and add chlorobenzene or cyclohexanone reagent to fully dissolve the precipitate; The solution after adding chlorobenzene or cyclohexanone reagent is diluted to obtain a nanosheet solution.

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