Preparation method and application of one-dimensional germanium triphosphide nanowire

Abstract

The invention provides a preparation method and application of a one-dimensional germanium triphosphide nanowire, and belongs to the technical field of preparation of germanium triphosphide. The one-dimensional germanium triphosphide crystal is prepared by adopting an electrochemical method, which is the first preparation of the material in a one-dimensional form. The one-dimensional germanium triphosphide nanowire is obtained by taking the germanium triphosphide polycrystalline block as a raw material and performing electrochemical preparation on the germanium triphosphide polycrystalline block by adopting an electrochemical dissociation-preparation technology, a brand new thought is provided for preparation of a low-dimensional material, and compared with a traditional preparation method of a one-dimensional material, the preparation method has the advantages of low energy consumption, less time consumption, low cost and easiness in operation. The one-dimensional germanium triphosphide nanowire prepared by the preparation method disclosed by the invention has the advantages of good conductivity, large specific surface area, high ion diffusion rate and the like as an electrode material, has huge application potential and wide development prospect as the electrode material of an energy storage device, and meanwhile, has good mechanical flexibility and can be applied to the field of energy storage devices. Therefore, the material has the potential of serving as an electrode material of novel energy storage devices such as flexible wearable devices and the like.

Description

Technical Field

[0001] This invention relates to the field of germanium triphosphide preparation technology, and more particularly to a method for preparing one-dimensional germanium triphosphide nanowires and their applications. Background Technology

[0002] Energy storage technology, as a key component of new energy sources, has attracted widespread attention. Developing efficient, economical, safe, and convenient energy storage technologies is of great significance. Among these, electrochemical capacitor energy storage technology has gained popularity due to its millisecond-level response capability, high conversion efficiency, long cycle life, and rapid charge-discharge characteristics. Electrode materials, as a key factor affecting the performance of energy storage devices, have been extensively studied. One-dimensional nanomaterials possess a high specific surface area, providing numerous active sites, thereby improving the specific capacity and energy density of energy storage devices (such as supercapacitors and lithium-ion batteries). Their one-dimensional structure can shorten the transport distance of ions and electrons, reduce diffusion resistance, and increase the charge-discharge rate of devices, while also enhancing their rate performance. The structure of one-dimensional materials can also alleviate the volume expansion problem of electrode materials during charge-discharge, extending the device's lifespan. The spatial structure of one-dimensional materials allows them to be combined with other materials, enabling rich structural control and performance optimization. Furthermore, the mechanical flexibility of one-dimensional materials makes them promising for applications in various novel energy storage devices, such as flexible wearable devices.

[0003] Germanium triphosphide (GNP) is a typical layered metallic phosphorus-based material that retains the unique wrinkled structure of black phosphorus. The introduction of metal atoms gives GNP its metallic properties. Its excellent conductivity significantly reduces electron transport resistance, decreases energy consumption, improves charge / discharge efficiency, and shortens response time. Simultaneously, its high conductivity reduces Joule heating caused by resistance, extending the cycle life of energy storage devices. Two-dimensional germanium triphosphide nanosheets, as a flexible solid-state supercapacitor material, exhibit high capacitance (46.67 F cm⁻¹). -3 Germanium triphosphide nanosheets exhibit excellent energy storage performance. However, during the preparation of electrode materials, two-dimensional germanium triphosphide nanosheets often undergo a "self-stacking" phenomenon, leading to a reduction in the specific surface area of ​​the nanosheets and thus affecting the electrochemical performance of the material. Porous structures formed by the interweaving of one-dimensional materials are typically macropores and mesopores. These pores are open, which facilitates the rapid migration of ions, and they are not as easily blocked as the micropores formed by the stacking of two-dimensional materials.

[0004] Therefore, one-dimensional germanium triphosphide nanowires have great application potential as electrode materials for energy storage devices. Summary of the Invention

[0005] Currently, the preparation of one-dimensional phosphides requires first synthesizing a precursor with a one-dimensional morphology, either a metal or a metal compound (such as an oxide or hydroxide), and then reacting it with a phosphorus source under a specific atmosphere to convert it into a metal phosphide while retaining its one-dimensional morphology. This process involves highly toxic PH3 gas, is hazardous, and requires sophisticated equipment. Therefore, to obtain one-dimensional germanium triphosphide nanowires, this invention provides a method for preparing one-dimensional germanium triphosphide nanowires and its application. Using germanium triphosphide polycrystalline blocks as raw materials, an electrochemical preparation method is employed to electrochemically prepare one-dimensional germanium triphosphide nanowires. This invention achieves the preparation of one-dimensional germanium triphosphide for the first time, and is also the first to use this method to prepare one-dimensional materials, providing a novel approach for the preparation of low-dimensional materials. Compared to traditional methods for preparing one-dimensional materials (arc discharge, chemical vapor deposition, laser sputtering, hydrothermal methods, etc.), this method has the advantages of low energy consumption, short processing time, low cost, and ease of operation.

[0006] To achieve the above objectives, the present invention provides the following technical solution: In a first aspect, the present invention provides a method for preparing one-dimensional germanium triphosphide nanowires, wherein a germanium triphosphide polycrystalline bulk is used as the cathode, a platinum sheet is used as the anode, and an alkaline solution is used as the electrolyte for electrochemical preparation to obtain one-dimensional germanium triphosphide nanowires. The alkaline solution concentration was less than 5 M. Electrochemical dissociation was performed under the following conditions: electrolysis at 20-25 V and 0.1 A, with an electrolysis time of 0 s < electrolysis time ≤ 10 s. Subsequent preparation at 5 V and 0.1 A for 30-70 min yielded nanowires with superior dimensions. These nanowires had diameters of 40-130 nm and lengths of 5-13 μm.

[0007] Secondly, this invention also provides the application of the aforementioned one-dimensional germanium triphosphide nanowires as electrode materials for energy storage devices. Its volumetric capacitance reaches as high as 77.49 F cm⁻¹. -3 The energy storage performance is higher than that of two-dimensional germanium triphosphide nanosheets (46.67 Fcm). -3 ).

[0008] The present invention provides a method for preparing one-dimensional germanium triphosphide nanowires and its application. Using germanium triphosphide polycrystalline blocks as raw materials, an electrochemical preparation method is employed to obtain one-dimensional germanium triphosphide nanowires. Compared with existing technologies, this method has the following advantages: (1) The present invention proposes a novel one-dimensional material preparation method, namely, electrochemical preparation technology. Using electrochemical dissociation-preparation technology, one-dimensional nanowires are directly electrochemically prepared from polycrystalline bulk germanium triphosphide, providing a novel approach for the preparation of low-dimensional materials; (2) The one-dimensional material prepared by this invention has a spatial structure and good conductivity, which makes it a promising electrode material for energy storage devices with great application potential and broad development prospects. As an electrode material, it has the advantages of large specific surface area, high ion diffusion rate, high charge and discharge efficiency, and short response time; at the same time, its good mechanical flexibility makes it a potential electrode material for new energy storage devices such as flexible wearable devices. (3) Electrochemical dissociation-preparation technology is used to realize the conversion of germanium triphosphide polycrystalline bulk into nanowires. Compared with traditional one-dimensional material preparation methods (arc discharge method, chemical vapor deposition method, laser sputtering method, hydrothermal method, etc.), it has the advantages of low energy consumption, short time consumption, low cost and easy operation. (4) The electrochemical dissociation-preparation method is used to realize the conversion of germanium triphosphide polycrystalline bulk into nanowires. The conditions are simple and it is expected to achieve large-scale mass production. Attached Figure Description

[0009] Figure 1 This is the XRD pattern of germanium triphosphide nanowires prepared in Example 1 of this application; Figure 2 These are scanned images of germanium triphosphide nanowires prepared in Example 1 of this application; Figure 3 This is a graph showing the energy storage performance of germanium triphosphide nanowires prepared in Example 1 of this application; Figure 4 These are scanned images of germanium triphosphide nanowires prepared in Example 2 of this application; Figure 5 These are scanned images of germanium triphosphide nanowires prepared in Example 3 of this application; Figure 6 These are scanned images of germanium triphosphide nanowires prepared in Example 4 of this application; Figure 7 These are scanned images of germanium triphosphide nanowires prepared in Example 5 of this application; Figure 8 These are scanned images of germanium triphosphide nanowires prepared in Example 6 of this application; Figure 9 These are scanned images of germanium triphosphide nanowires prepared in Example 7 of this application; Figure 10 These are scanned images of germanium triphosphide nanowires prepared in Example 8 of this application; Figure 11 These are scanned images of germanium triphosphide nanowires prepared in Example 9 of this application; Figure 12 These are scanning images of germanium triphosphide nanowires prepared in Comparative Example 1 of this application; Figure 13 These are the XRD patterns of the samples prepared in Examples 4 and 9 of this application. Detailed Implementation

[0010] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0011] This invention provides a method for preparing one-dimensional germanium triphosphide nanowires, which uses a polycrystalline germanium triphosphide bulk as the cathode, a platinum electrode as the anode, and an alkaline solution as the electrolyte for electrochemical dissociation to obtain one-dimensional germanium triphosphide nanowires. Specifically: Germanium triphosphide polycrystalline bulk material was used as the cathode, a platinum electrode as the anode, and an alkaline solution as the electrolyte for electrochemical preparation. The resulting solution was vacuum filtered, washed, and dried to obtain germanium triphosphide nanowires. Preferably, the alkaline solution was a NaOH solution with a concentration below 5 M, and preferably contained OH-. - The concentration is less than 5 M, and more preferably, the concentration of the alkaline solution is 0.5 M.

[0012] In this invention, the electrochemical dissociation conditions are: electrolysis time of 30-70 min, electrolysis voltage within 30 V, and electrolysis current within 0.5 A. Excessive voltage and current cause cations to rapidly insert into the germanium triphosphide interlayer, producing a large number of two-dimensional germanium triphosphide sheets, resulting in only a very small number of nanowires. Selecting a single voltage and current condition during the preparation process can only yield a small amount of germanium triphosphide nanowires. In one implementation, this invention employs a two-stage electrolysis process: specifically, the preferred electrochemical dissociation conditions are a voltage of 20-25 V, a current of 0.1 A, and an electrolysis time of 0 s < electrolysis time ≤ 10 s; followed by preparation at a voltage of 5 V and a current of 0.1 A for 30-70 min. These voltage and current conditions for electrochemical preparation can achieve a large-scale transformation of germanium triphosphide from polycrystalline bulk to nanowires. The preferred electrochemical dissociation conditions are electrolysis at 20 V and 0.1 A for 10 s, followed by preparation at 5 V and 0.1 A for 50-70 min. Experimental studies show that under the first stage of 20 V and 0.1 A, the longer the electrolysis time within 0-10 s, the more nanowire generation sites are generated, and the greater the number of nanowires produced. However, the longer the electrolysis time exceeds 10 s, the fewer nanowires are produced. Under the second stage of 5 V and 0.1 A, the longer the preparation time within 30-50 min, the longer the nanowires are. Within the 50-70 min electrolysis time, the nanowires produced all exhibit excellent dimensions. Therefore, in this invention, the preferred electrochemical dissociation conditions are electrolysis at a voltage of 20 V and a current of 0.1 A for 10 s; the preferred electrochemical preparation conditions are preparation at a voltage of 5 V and a current of 0.1 A for 50-70 min, which can yield a large number of nanowires with diameters of 40-130 nm and lengths of 5-13 μm.

[0013] In this invention, germanium triphosphide polycrystalline bulk material can be prepared using any existing preparation method. This invention exemplarily provides a method for synthesizing germanium triphosphide polycrystalline bulk material using a high-temperature, high-pressure (HTHP) method. The HTHP method preferably uses a pressure of 1-6 GPa, more preferably 2 GPa; a temperature of 300-700 °C, more preferably 500-600 °C; and a time of 5-30 min, more preferably 10 min.

[0014] This invention also includes vacuum filtration, washing, and drying of the solution after electrochemical dissociation. Specifically: Germanium triphosphide polycrystalline bulk material was used as the cathode, platinum electrode as the anode, and NaOH solution as the electrolyte for electrochemical preparation. The resulting solution was vacuum filtered, washed, and dried to obtain germanium triphosphide nanowires.

[0015] The vacuum filtration process can be achieved by selecting any type of water-based filter membrane resistant to strong alkali. In one implementation method, the filter membrane is preferably a PTFE membrane, i.e., a polytetrafluoroethylene membrane, and the pore size of the filter membrane is preferably 220 nm.

[0016] In this invention, the washing process can be carried out by any washing method to remove electrolyte ions. In one implementation, deionized water is added to the sample after vacuum filtration, and vacuum filtration is performed repeatedly to remove alkaline solution from the sample.

[0017] In this invention, the drying process can be implemented using any of the methods in the prior art. In one implementation, the drying method uses a heating table; the temperature of the heating table is limited to 60-100 ℃, and the drying time is 20-60 min.

[0018] The one-dimensional germanium triphosphide nanowires prepared by this invention, as electrode materials, have good conductivity, large specific surface area, high ion diffusion rate, and high charge-discharge efficiency, which makes them have great application potential and broad development prospects as electrode materials for energy storage devices. At the same time, their good mechanical flexibility makes them potential as electrode materials for new energy storage devices such as flexible wearable devices.

[0019] The technical solution of the present invention will be clearly and thoroughly described below with reference to specific embodiments.

[0020] Example 1 (1) Germanium triphosphide polycrystalline bulk was prepared by high temperature and high pressure method, with a sintering temperature of 500 ℃, a sintering pressure of 2 GPa, and a holding time of 10 minutes.

[0021] (2) Using the sintered germanium triphosphide polycrystalline bulk as the cathode, a platinum electrode as the anode, and 40 mL of 0.5 M NaOH as the electrolyte, electrochemical dissociation-preparation was performed. The electrochemical dissociation conditions were: dissociation at 20 V and 0.1 A for 10 s, followed by preparation at 5 V and 0.1 A for 1 h.

[0022] (3) Using vacuum filtration, a filter membrane with a pore size of 220 nm is used to filter the above-dissociated solution to obtain a thin film with the attached sample.

[0023] (4) Add deionized water to the filtration device and wash repeatedly to remove residual NaOH from the sample.

[0024] (5) Place the film with the attached sample on the heating table and dry it at 70 °C for 30 min.

[0025] The XRD image of the sample is as follows Figure 1As shown, this indicates that the one-dimensional sample we prepared is germanium triphosphide. The SEM image of this sample is shown below. Figure 2 As shown, the above preparation conditions can successfully prepare a large number of germanium triphosphide nanowires, effectively realizing the transformation of germanium triphosphide from a polycrystalline bulk to one-dimensional nanowires. The prepared nanowires have a radial dimension of 40-130 nm and a length of 5-13 μm, exhibiting excellent size characteristics. This is the first time one-dimensional germanium triphosphide has been prepared using this invention. Previously, one-dimensional germanium triphosphide nanowires could not be prepared; germanium triphosphide only had two structures: bulk and two-dimensional nanosheets. Therefore, this invention compares the performance of the prepared one-dimensional germanium triphosphide nanowires with that of two-dimensional nanosheets. Specifically, as shown... Figure 3 As shown, the one-dimensional germanium triphosphide nanowires prepared in Example 1 of this invention, used as the electrode material for a supercapacitor, exhibit a volumetric capacitance as high as 77.49 Fcm. -3 Its energy storage performance is higher than that of two-dimensional germanium triphosphide nanosheets (46.67 F cm⁻¹). -3 ).

[0026] Example 2 (1) Germanium triphosphide polycrystalline bulk was prepared by high temperature and high pressure method, with a sintering temperature of 500℃, a sintering pressure of 2GPa, and a holding time of 10 minutes.

[0027] (2) The sintered germanium triphosphide polycrystalline bulk was used as the cathode, a platinum electrode as the anode, and 40 mL of 0.5 M NaOH as the electrolyte for electrochemical dissociation. The electrochemical dissociation conditions were: dissociation at 20 V and 0.1 A for 10 s, followed by dissociation at 5 V and 0.1 A for 50 min.

[0028] (3) Using vacuum filtration, a filter membrane with a pore size of 220 nm is used to filter the above-dissociated solution to obtain a thin film with the attached sample.

[0029] (4) Add deionized water to the filtration device and wash repeatedly to remove residual NaOH from the sample.

[0030] (5) Place the film with the attached sample on the heating table and dry it at 70°C for 30 min.

[0031] The SEM image of the sample is as follows Figure 4 As shown, the above preparation conditions can successfully prepare large quantities of germanium triphosphide nanowires, effectively realizing the transformation of germanium triphosphide from polycrystalline bulk to one-dimensional nanowires. The prepared nanowires have radial dimensions of 40-130 nm and lengths of 5-13 μm, exhibiting excellent dimensional properties.

[0032] Example 3 (1) Germanium triphosphide polycrystalline bulk was prepared by high temperature and high pressure method, with a sintering temperature of 500 ℃, a sintering pressure of 2 GPa, and a holding time of 10 minutes.

[0033] (2) The sintered germanium triphosphide polycrystalline bulk was used as the cathode, a platinum electrode as the anode, and 40 mL of 0.5 M NaOH as the electrolyte for electrochemical dissociation. The electrochemical dissociation conditions were: dissociation at 20 V and 0.1 A for 10 s, followed by dissociation at 5 V and 0.1 A for 70 min.

[0034] (3) Using vacuum filtration, a filter membrane with a pore size of 220 nm is used to filter the above-dissociated solution to obtain a thin film with the attached sample.

[0035] (4) Add deionized water to the filtration device and wash repeatedly to remove residual NaOH from the sample.

[0036] (5) Place the film with the attached sample on the heating table and dry it at 70 °C for 30 min.

[0037] The SEM image of the sample is as follows Figure 5 As shown, the above preparation conditions can successfully prepare large quantities of germanium triphosphide nanowires, effectively realizing the transformation of germanium triphosphide from polycrystalline bulk to one-dimensional nanowires. The prepared nanowires have radial dimensions of 40-130 nm and lengths of 5-13 μm, exhibiting excellent dimensional properties.

[0038] Examples 1, 2, and 3 show that for germanium triphosphide polycrystalline materials sintered at 500 °C under a pressure of 2 GPa, electrolysis at 20 V and 0.1 A for 10 s followed by preparation at 5 V and 0.1 A for 50-70 min yields one-dimensional germanium triphosphide nanowires with excellent dimensions, ranging from 40-130 nm in diameter and 5-13 μm in length.

[0039] Example 4 (1) Germanium triphosphide polycrystalline bulk was prepared by high temperature and high pressure method. The sintering temperature was 600 ℃, the sintering pressure was 2 GPa, and the holding time was 10 minutes.

[0040] (2) The sintered germanium triphosphide polycrystalline bulk was used as the cathode, a platinum electrode as the anode, and 40 mL of 0.5 M NaOH as the electrolyte for electrochemical dissociation. The electrochemical dissociation conditions were: dissociation at 20 V and 0.1 A for 10 s, followed by dissociation at 5 V and 0.1 A for 50 min.

[0041] (3) Using vacuum filtration, a filter membrane with a pore size of 220 nm is used to filter the above-dissociated solution to obtain a thin film with the attached sample.

[0042] (4) Add deionized water to the filtration device and wash repeatedly to remove residual NaOH from the sample.

[0043] (5) Place the film with the attached sample on the heating table and dry it at 70 °C for 30 min.

[0044] The SEM image of the sample is as follows Figure 6 As shown, the above preparation conditions can successfully prepare large quantities of germanium triphosphide nanowires, effectively realizing the transformation of germanium triphosphide from polycrystalline bulk to one-dimensional nanowires. From... Figure 6 It can be seen that the product contains nanowires and some undissociated bulk material. XRD tests were performed on the sample. Figure 13 It can be seen that both the generated nanowires and the undissociated bulk are germanium triphosphide, and no new phase is generated in this process.

[0045] Example 5 (1) Germanium triphosphide polycrystalline bulk was prepared by high temperature and high pressure method. The sintering temperature was 600 ℃, the sintering pressure was 2 GPa, and the holding time was 10 minutes.

[0046] (2) The sintered germanium triphosphide polycrystalline bulk was used as the cathode, a platinum electrode as the anode, and 40 mL of 0.5 M NaOH as the electrolyte for electrochemical dissociation. The electrochemical dissociation conditions were: dissociation at 20 V and 0.1 A for 10 s, followed by dissociation at 5 V and 0.1 A for 1 h.

[0047] (3) Using vacuum filtration, a filter membrane with a pore size of 220 nm is used to filter the above-dissociated solution to obtain a thin film with the attached sample.

[0048] (4) Add deionized water to the filtration device and wash repeatedly to remove residual NaOH from the sample.

[0049] (5) Place the film with the attached sample on the heating table and dry it at 70 °C for 30 min.

[0050] The SEM image of the sample is as follows Figure 7 As shown, the above preparation conditions can successfully prepare a large number of germanium triphosphide nanowires, and can effectively realize the transformation of germanium triphosphide from polycrystalline bulk to one-dimensional nanowires.

[0051] Examples 5 and 6 show that germanium triphosphide polycrystalline material sintered at 600 °C under a pressure of 2 GPa can also be used as a raw material to successfully prepare one-dimensional germanium triphosphide nanowires.

[0052] Example 6 (1) Germanium triphosphide polycrystalline bulk was prepared by high temperature and high pressure method, with a sintering temperature of 500 ℃, a sintering pressure of 2 GPa, and a holding time of 10 minutes.

[0053] (2) The sintered germanium triphosphide polycrystalline bulk was used as the cathode, a platinum electrode as the anode, and 40 mL of 0.5 M NaOH as the electrolyte for electrochemical dissociation. The electrochemical dissociation conditions were: dissociation at 25 V and 0.1 A for 10 s, followed by dissociation at 5 V and 0.1 A for 1 h.

[0054] (3) Using vacuum filtration, a filter membrane with a pore size of 220 nm is used to filter the above-dissociated solution to obtain a thin film with the attached sample.

[0055] (4) Add deionized water to the filtration device and wash repeatedly to remove residual NaOH from the sample.

[0056] (5) Place the film with the attached sample on the heating table and dry it at 70 °C for 30 min.

[0057] The SEM image of the sample is as follows Figure 8 As shown, the above preparation conditions can successfully prepare a large number of germanium triphosphide nanowires, and can effectively realize the transformation of germanium triphosphide from polycrystalline bulk to one-dimensional nanowires.

[0058] Example 7 (1) Germanium triphosphide polycrystalline bulk was prepared by high temperature and high pressure method, with a sintering temperature of 500 ℃, a sintering pressure of 2 GPa, and a holding time of 10 minutes.

[0059] (2) The sintered germanium triphosphide polycrystalline bulk was used as the cathode, a platinum electrode as the anode, and 40 mL of 0.5 M NaOH as the electrolyte for electrochemical dissociation. The electrochemical dissociation conditions were: dissociation at 20 V and 0.1 A for 10 s, followed by dissociation at 5 V and 0.1 A for 40 min.

[0060] (3) Using vacuum filtration, a filter membrane with a pore size of 220 nm is used to filter the above-dissociated solution to obtain a thin film with the attached sample.

[0061] (4) Add deionized water to the filtration device and wash repeatedly to remove residual NaOH from the sample.

[0062] (5) Place the film with the attached sample on the heating table and dry it at 70 °C for 30 min.

[0063] The SEM image of the sample is as follows Figure 9 As shown, the above preparation conditions can successfully prepare germanium triphosphide nanowires, but the length of the germanium triphosphide nanowires is relatively short. (Random statistics) Figure 9 The lengths of the 100 nanowires are shown in the figure. Figure 9 The illustration shows that the average length of the nanowires prepared under these conditions is only 0.77 μm.

[0064] Example 8 (1) Germanium triphosphide polycrystalline bulk was prepared by high temperature and high pressure method. The sintering temperature was 500 ℃, the sintering pressure was 2 GPa, and the holding time was 10 minutes.

[0065] (2) The sintered germanium triphosphide polycrystalline bulk was used as the cathode, a platinum electrode as the anode, and 40 mL of 0.5 M NaOH as the electrolyte for electrochemical dissociation. The electrochemical dissociation conditions were: dissociation at 20 V and 0.1 A for 8 s, followed by dissociation at 5 V and 0.1 A for 30 min.

[0066] (3) Using vacuum filtration, a filter membrane with a pore size of 220 nm is used to filter the above-dissociated solution to obtain a thin film with the attached sample.

[0067] (4) Add deionized water to the filtration device and wash repeatedly to remove residual NaOH from the sample.

[0068] (5) Place the film with the attached sample on the heating table and dry it at 70 °C for 30 min.

[0069] The SEM image of the sample is as follows Figure 10 As shown, the above preparation conditions result in a relatively small amount of germanium triphosphide nanowires.

[0070] Example 9 (1) Germanium triphosphide polycrystalline bulk was prepared by high temperature and high pressure method. The sintering temperature was 500 ℃, the sintering pressure was 2 GPa, and the holding time was 10 minutes.

[0071] (2) The sintered germanium triphosphide polycrystalline bulk was used as the cathode, a platinum electrode as the anode, and 40 mL of 0.5 M NaOH as the electrolyte for electrochemical dissociation. The electrochemical dissociation conditions were: dissociation at 20 V and 0.1 A for 10 s, followed by dissociation at 5 V and 0.1 A for 30 min.

[0072] (3) Using vacuum filtration, a filter membrane with a pore size of 220 nm is used to filter the above-dissociated solution to obtain a thin film with the attached sample.

[0073] (4) Add deionized water to the filtration device and wash repeatedly to remove residual NaOH from the sample.

[0074] (5) Place the film with the attached sample on the heating table and dry it at 70 °C for 30 min.

[0075] The SEM image of the sample is as follows Figure 11 As shown, comparison Figure 8 This indicates that increasing the electrolysis time from 8 s to 10 s at 20V resulted in a greater quantity of nanowires produced. Subsequently, statistics were compiled. Figure 11 The lengths of the 200 nanowires are shown in the figure. Figure 11 The illustration shows that the average length of the nanowires prepared under these conditions is 0.55 μm.

[0076] right Figure 11 The sample shown was subjected to XRD testing (e.g. Figure 13 This indicates that no new phase is formed in the early stages of nanowire formation.

[0077] The above examples demonstrate that germanium triphosphide nanowires can be successfully prepared by using a polycrystalline bulk of germanium triphosphide powder sintered at 2 GPa and 500-600℃ as the cathode, 0.5 M NaOH as the electrolyte, and a platinum electrode as the anode for electrochemical dissociation, thus achieving the transformation of germanium triphosphide polycrystalline bulk into one-dimensional nanowires. The optimal electrochemical dissociation conditions are: first, dissociation at 20-25 V and 0.1 A for 10 s, followed by dissociation at 5 V and 0.1 A for 50-70 min. These conditions can successfully prepare large quantities of germanium triphosphide nanowires with excellent dimensions.

[0078] Comparing the results of Examples 8 and 9, as follows Figure 10 , 11 As shown, when the electrolysis time at 20 V and 0.1 A is increased from 8 s to 10 s, the number of nanowire generation sites increases, and the number of nanowires increases.

[0079] Comparing the results of Examples 1, 2, 3, 7, and 9, as follows: Figure 2 , 4 As shown in Figures 5, 9, and 11, the nanowires were first electrolyzed at 20 V and 0.1 A for 10 s, then prepared at 5 V and 0.1 A. The preparation time at 5 V was increased from 30 min to 40 min, and then to 50 min, resulting in longer nanowires. The corresponding SEM images are as follows: Figure 11 , 94. The average length of the nanowires increased from 0.55 μm to 0.77 μm, and then to more than 5 μm; when the electrolysis time was 50-70 min at 5 V, the length of the nanowires was more than 5 μm, showing excellent size.

[0080] contrast Figure 1 , 13 It can be seen that no new phase is formed during the electrolytic preparation of nanowires from germanium triphosphide bulk material. The XRD peaks of all products with different morphologies produced during the electrochemical dissociation process, including the polycrystalline bulk material, the generated nanowires, and incompletely electrolyzed fragments, all correspond to the standard card for germanium triphosphide, indicating that no new phase is introduced during the entire electrochemical dissociation process.

[0081] Comparative Example 1 (1) Germanium triphosphide polycrystalline bulk was prepared by high temperature and high pressure method. The sintering temperature was 500 ℃, the sintering pressure was 2 GPa, and the holding time was 10 minutes.

[0082] (2) The sintered germanium triphosphide polycrystalline bulk was used as the cathode, a platinum electrode as the anode, and 40 mL of 0.5 M NaOH as the electrolyte for electrochemical dissociation. The electrochemical dissociation conditions were 5 V voltage and 0.1 A current for 60 min.

[0083] (3) Using vacuum filtration, a filter membrane with a pore size of 220 nm is used to filter the above-dissociated solution to obtain a thin film with the attached sample.

[0084] (4) Add deionized water to the filtration device and wash repeatedly to remove residual NaOH from the sample.

[0085] (5) Disperse the sample in alcohol using ultrasound, drop the sample dispersion onto the silicon wafer, place the silicon wafer on a heating stage, and dry the liquid inside.

[0086] The SEM image of the sample is as follows Figure 12 As shown, this condition can achieve the transformation of germanium triphosphide polycrystalline bulk to nanowires; however, comparing the two voltage conditions of different magnitudes in Example 1, i.e., comparing... Figure 12 and Figure 2 (All nanowires are over 5 μm in length). When electrolyzed under a single voltage and current condition, the amount of nanowires transformed is extremely small, and the resulting nanowires are relatively short (e.g., ...). Figure 12 Due to the medium diameter (~2.83 μm), large-scale preparation of germanium triphosphide nanowires is not possible.

[0087] The above description is merely a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and its improved concept, should be covered within the scope of protection of the present invention.

Claims

1. A method for preparing one-dimensional germanium triphosphide nanowires, characterized in that, One-dimensional germanium triphosphide nanowires were prepared by electrochemically using a polycrystalline bulk germanium triphosphide as the cathode and an alkaline solution as the electrolyte. The alkaline solution concentration was less than 5 M, and the electrochemical preparation conditions were a voltage of 20-25 V, a current of 0.1 A, dissociation time of 0 s < preparation time ≤ 10 s, followed by preparation at a voltage of 5 V and a current of 0.1 A for 30-70 min.

2. The method for preparing one-dimensional germanium triphosphide nanowires according to claim 1, characterized in that, The concentration of the alkaline solution is 0.5 M.

3. The method for preparing one-dimensional germanium triphosphide nanowires according to claim 1, characterized in that, Electrolysis was performed at 20 V and 0.1 A for 10 s, followed by preparation at 5 V and 0.1 A for 50-70 min.

4. The method for preparing one-dimensional germanium triphosphide nanowires according to claim 1, characterized in that, Germanium triphosphide polycrystalline bulk was synthesized using a high-temperature and high-pressure method.

5. The method for preparing one-dimensional germanium triphosphide nanowires according to claim 4, characterized in that, The high-temperature and high-pressure method uses a pressure of 1-6 GPa, a temperature of 300-700 ℃, and a time of 5-30 min.

6. The method for preparing one-dimensional germanium triphosphide nanowires according to claim 5, characterized in that, The pressure was 2 GPa, the temperature was 500-600 ℃, and the time was 10 min.

7. The method for preparing one-dimensional germanium triphosphide nanowires according to claim 1, characterized in that, It also includes vacuum filtration, washing, and drying of the solution after electrochemical preparation.

8. The method for preparing one-dimensional germanium triphosphide nanowires according to claims 1-7, characterized in that, The alkaline solution is a NaOH solution.

9. A one-dimensional germanium triphosphide nanowire, characterized in that, It is prepared by the preparation method of any one of claims 1-8, and has a diameter of 40-130 nm and a length of 6-13 μm.

10. The application of the one-dimensional germanium triphosphide nanowire as described in claim 9 as an electrode material for energy storage devices.

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