A preparation method for improving hydrogen response performance of hydrogen-induced color change film

Abstract

This invention discloses a method for preparing hydrogen-responsive magnesium-based thin films with improved hydrogen-chromic properties. The method includes adjusting the argon flow rate to 20 sccm–100 sccm during the magnetron sputtering process to prepare the magnesium-based hydrogen-sensitive reaction layer. This invention utilizes the control of the argon flow rate during magnetron sputtering to influence the sputtered atom collision frequency and mean free path, thereby altering the film growth conditions and microstructure, and conveniently and rapidly improving the hydrogen absorption and desorption rates of the hydrogen-chromic thin film. This method is simple, highly reproducible, and significantly improves performance, showing significant application potential in the field of hydrogen sensing.

Description

Technical Field

[0001] This invention belongs to the field of hydrogen-chromatic thin film technology, specifically relating to a preparation method for improving the hydrogen adsorption and dehydrogenation response performance of hydrogen-chromatic thin films. Background Technology

[0002] With the increasing global demand for renewable and clean energy, hydrogen, as a clean and efficient energy carrier, is finding increasingly widespread applications, including energy storage, fuel cell vehicles, aerospace, and urban gas supply. However, hydrogen poses certain dangers. It is flammable and explosive, with a low ignition point energy and a wide explosive concentration range. When mixed with air, its volume ratio between 4% and 75% can easily explode upon contact with an open flame. Furthermore, hydrogen molecules have a low density and diffuse easily, allowing them to penetrate the crystal lattice of many metals, causing "hydrogen embrittlement." Special storage materials are required during the storage, transportation, and use of hydrogen, and leaks must be prevented. In addition, hydrogen is colorless and odorless, making it undetectable to the human senses at first glance.

[0003] Therefore, monitoring hydrogen concentration and preventing leaks are crucial for avoiding accidents and ensuring personnel safety during the production, storage, transportation, and utilization of hydrogen. Industry and research institutions are increasingly emphasizing hydrogen safety. There is an urgent need for industries to equip themselves with high-response, high-sensitivity, and reliable hydrogen sensors.

[0004] With the continuous development of sensor technology, various types of hydrogen sensors have been developed, including electrochemical sensors, nanomaterial sensors, semiconductor sensors, and optical sensors. These sensors can quickly and accurately detect hydrogen concentration and have better sensitivity and reliability. Among them, optical hydrogen sensors have the advantages of not requiring electrodes and electrolytes; having no contact materials and a simple structure; and being relatively less affected by moisture and pollution. Hydrogen sensors based on hydrogen-chromic thin films are one of the current research directions for optical hydrogen sensors. The most representative hydrogen-chromic thin film structure is palladium / magnesium-based composite material / quartz glass. Existing composite materials include transition metals, rare earth metals, alkaline earth metals, and transition metal oxides, and their performance mainly depends on the microstructure of the hydrogen-chromic thin film. However, the hydrogen adsorption / desorption rate and cycle durability of existing magnesium-based hydrogen-chromic thin films still need to be further improved to meet the response and durability requirements of hydrogen sensors.

[0005] Hydrochromic magnesium-based thin films are typically prepared using magnetron sputtering. Current research on the performance regulation of hydrochromic films mainly focuses on adjusting the elemental composition ratio through sputtering power and the film thickness through sputtering time. However, it is difficult to directly adjust the microstructure of the film. Controlling the argon flow rate can achieve this better. With changes in argon flow rate, the sputtered atom collision frequency and mean free path change significantly. At low flow rates, target atoms easily deposit on the substrate at a faster rate. At high flow rates, the deposition rate is relatively slower due to the increased number of collisions with argon atoms in the atmosphere. As the argon flow rate increases, the film gradually evolves from a dense structure to a microporous structure. For hydrochromic films, without compromising film integrity, the relatively porous structure helps increase the specific surface area, promotes hydrogen diffusion, and thus accelerates the hydrogen absorption and desorption rates, which is beneficial for improving film performance. Therefore, the influence of argon flow rate on the performance of hydrochromic films is of great research value. Summary of the Invention

[0006] The purpose of this invention is to overcome the shortcomings of the prior art and provide a method for preparing a hydrogen-induced color-changing film with improved hydrogen absorption and dehydrogenation response performance. This method and its application improve the performance of magnesium-based hydrogen-induced color-changing films by directly adjusting the film microstructure, and has the advantages of simple operation and fast hydrogen absorption and dehydrogenation rate.

[0007] The objective of this invention is achieved through the following technical solution:

[0008] In a first aspect, the present invention provides a method for preparing a hydrogen-responsive thin film with improved hydrogen chromatic properties, including adjusting the argon flow rate in the magnetron sputtering process to 20 sccm to 100 sccm during the preparation of a magnesium-based hydrogen-sensitive reaction layer using magnetron sputtering.

[0009] As a preferred embodiment, the controlled argon gas flow rate is 20 sccm to 80 sccm; more preferably, the argon gas flow rate is 40 sccm.

[0010] As a preferred embodiment, the material of the magnesium-based hydrogen-sensitive reaction layer is any one of magnesium-rare earth, magnesium-transition metal, or magnesium-transition metal oxide.

[0011] As a preferred embodiment, the magnesium-based hydrogen-sensitive reaction layer is any one of a magnesium-scandium film layer, a magnesium-yttrium film layer, or a magnesium-gadolinium film layer.

[0012] As a preferred embodiment, the thickness of the magnesium-based hydrogen-sensitive reaction layer is 10–100 nm.

[0013] As a preferred embodiment, the method specifically includes the following steps:

[0014] S1. Perform surface cleaning pretreatment on the substrate to keep the surface clean and dry;

[0015] S2. A magnesium-based hydrogen-sensitive reaction layer is deposited on the pretreated substrate using DC magnetron sputtering co-sputtering. During the deposition process, the flow rate of argon gas is controlled to be 20 sccm to 100 sccm to adjust the microstructure of the film.

[0016] S3. A catalyst layer is deposited in situ on the magnesium-based hydrogen-sensitive reaction layer by DC magnetron sputtering, so that it inherits the microstructure formed in step S2.

[0017] S4. A polymer layer is deposited on the catalyst layer using chemical vapor deposition.

[0018] As a preferred embodiment, in step S2, the target material used is a magnesium target and other element targets; the other element targets are selected from any one of rare earth element targets, transition metal targets, and transition metal oxide targets; the sputtering power of the magnesium target is 30-200W, the sputtering power of the other element targets is 40-300W, and the total sputtering time is 30-100s.

[0019] As a preferred embodiment, the controlled argon gas flow rate is 20 sccm to 80 sccm; more preferably, it is 40 sccm. In the preparation method, high-purity argon is used as the working gas. The argon ions generated after ionization can bombard the target material to excite target ions without reacting with them, thus having no effect on the film composition. Changing the argon flow rate can affect the sputtering atom collision frequency and mean free path, thereby altering the film growth conditions and microstructure. The film thickness can be maintained between 10-100 nm by adjusting the argon flow rate. Further experimental studies have shown that excessively low argon flow rates prevent the target material from glowing, hindering sputtering; excessively high argon flow rates can damage the integrity of the film structure, affecting the performance of the obtained hydrogen-chromic film.

[0020] As a preferred embodiment, in step S3, when depositing the catalyst layer, the sputtering power of the target material is 50–100 W, and the sputtering time is 10–60 s. Excessive sputtering time and excessively high sputtering power will damage the microstructure in step S2, while insufficient sputtering time will result in inadequate catalyst coverage, affecting the catalytic effect.

[0021] As a preferred embodiment, the catalyst layer is made of Pd, Pt, or an alloy containing Pd.

[0022] As a preferred embodiment, in step S4, the polymer layer is a highly hydrophobic transparent polymer film layer, and the material is selected from any one of fluoropolymers, polymethyl methacrylate, and polytetrafluoroethylene.

[0023] As a preferred embodiment, in steps S2 and S3, before sputtering the target, a pre-sputtering cleaning step is also included; during the pre-sputtering, there should be a vertical baffle in front of the target to ensure the removal of contaminants and oxide layers on the target surface, and also to prevent target ions from sputtering onto the substrate. The baffle is opened during deposition.

[0024] Secondly, the present invention also provides a hydrogen-induced color-changing thin film prepared according to the aforementioned method.

[0025] Compared with the prior art, the present invention has the following beneficial effects:

[0026] 1) In the preparation of thin films by magnetron sputtering, the change of argon flow rate can affect the collision frequency and mean free path of sputtered atoms, thereby changing the conditions for thin film growth. The preparation process of this invention is stable, easy to control, highly repeatable, applicable to different thin films, and has promotional significance.

[0027] 2) The preparation process of this thin film is simple. It only requires changing the flow rate of argon gas during sputtering. No additional operation is required, and the process can be easily adjusted according to actual needs.

[0028] 3) The catalytic film layer sputtered in situ under vacuum conditions can prevent the magnesium-based hydrogen-sensitive reaction layer from being oxidized. At the same time, the catalytic layer inherits the microstructure formed by the magnesium-based hydrogen-sensitive reaction layer, which improves the hydrogen absorption and dehydrogenation rate of the film.

[0029] 4) This invention regulates the internal microstructure of the film and expands the specific surface area of ​​the film through micropores and other means, which provides a path for hydrogen diffusion, thereby having a faster hydrogenation rate and dehydrogenation rate.

[0030] 5) The hydrogen-chromatic thin films prepared by this method are low in cost, have faster hydrogen absorption and dehydrogenation times, especially dehydrogenation times, a wide range of optical changes, and long cycle life, and have important application prospects in the field of hydrogen sensors. Attached Figure Description

[0031] Other features, objects, and advantages of the present invention will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings:

[0032] Figure 1 This is a schematic diagram of the membrane structure, showing the location of the membrane layer where the argon flow rate is adjusted.

[0033] Figure 2 This is a schematic diagram of hydrogen absorption curves of hydrogen-chromic films prepared with different argon flow rates in an embodiment of the present invention, illustrating the effect of the method on adjusting the hydrogen absorption rate of the film.

[0034] Figure 3This is a schematic diagram of hydrogen desorption curves of hydrogen-chromic films prepared with different argon flow rates in an embodiment of the present invention, illustrating the effect of the method on adjusting the hydrogen desorption rate of the film.

[0035] Figure 4 This is a schematic diagram showing the AFM morphology and roughness of hydrogen-induced color-changing films prepared with different argon flow rates in an embodiment of the present invention, illustrating the effect of the method on adjusting the microstructure of the film. Detailed Implementation

[0036] The present invention will now be described in detail with reference to specific embodiments. These embodiments will help those skilled in the art to further understand the present invention, but do not limit the invention in any way. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention. These all fall within the scope of protection of the present invention.

[0037] Example 1

[0038] This embodiment provides a method for preparing a hydrogen-chromatic thin film with improved hydrogen adsorption and dehydrogenation response performance. The method involves adjusting the argon flow rate during the sputtering process of the hydrogen-chromatic thin film to prepare a fluorocarbon / palladium / magnesium-scandium hydrogen-chromatic thin film, and includes the following steps:

[0039] (1) Soak the quartz glass slide in a mixed solution of concentrated sulfuric acid and hydrogen peroxide (volume ratio 3:1), then rinse the quartz glass slide with deionized water; place the cleaned quartz glass slide into the magnetron sputtering reaction chamber, turn on the vacuum system to evacuate to a background vacuum of 3×10⁻⁶. -4 Pa.

[0040] (2) Heat the substrate to a temperature of 20–25°C, introduce working gas A (argon), and maintain a pressure of 0.4–0.6 Pa. After the pressure stabilizes, turn on the power to the palladium, magnesium, and scandium targets, turn off the baffles in front of each target, and pre-sputter clean the targets for 10 min. Then set the co-sputtering process program, with sputtering powers of 40 W and 100 W for the magnesium and scandium targets, respectively, adjusting the argon flow rate to 20 sccm, and the co-sputtering time to 60 s. Begin depositing the magnesium-scandium thin film with a thickness of 50 nm.

[0041] (3) After deposition, under the condition of maintaining a vacuum of 0.5 Pa, the sputtering process of the palladium catalyst layer is loaded, and the sputtering power of the palladium target is adjusted to 80 W, the sputtering time to 14 s, and the film thickness to 5 nm. After the palladium film growth is completed, the power supply of all target materials is turned off, and the sample is continued to be purged with working gas A (argon). Then the sample is taken out to obtain a thin film with the composition of Pd / Mg-Sc.

[0042] (4) The Pd / Mg-Sc thin film was placed in a reactive ion vapor deposition (RIVDC) machine. The process parameters for the fluorocarbon film were set as follows: working gas pressure 4 Pa, working gas (C4F8) flow rate 40 sccm, gas excitation power 600 W, and deposition time 60 s. The working gas was introduced, the process program was loaded, and the fluorocarbon film was deposited to a thickness of 100 nm. After completion, the sample was removed, yielding a CF / Pd / Mg-Sc thin film. The structure of the obtained film is shown below. Figure 1 As shown, it includes a magnesium-scandium composite film layer (Mg-Sc layer), a palladium catalyst layer (Pd layer), and a fluorocarbon film layer (FC layer) sequentially disposed on a substrate.

[0043] A schematic diagram of the transmittance curve of the hydrogen absorption process of the obtained CF / Pd / Mg-Sc thin film is shown below. Figure 2 As shown (the curve represented by 20 sccm), by Figure 2 It can be seen that the hydrogen absorption reaction time of the CF / Pd / Mg-Sc thin film is about 3.9 s.

[0044] A schematic diagram of the transmittance curve of the hydrogen desorption process of the obtained CF / Pd / Mg-Sc thin film is shown below. Figure 3 As shown (the curve represented by 20 sccm), by Figure 3 It can be seen that the hydrogen release reaction time of the CF / Pd / Mg-Sc thin film is approximately 123.5 s.

[0045] AFM results for CF / Pd / Mg-Sc thin films are as follows: Figure 4 As shown in a, by Figure 4 As can be seen from a, the roughness Rq of the CF / Pd / Mg-Sc thin film is approximately 0.679 nm.

[0046] Example 2

[0047] This embodiment provides a method for preparing a hydrogen-chromatic thin film with improved hydrogen adsorption and dehydrogenation response performance. The method involves adjusting the argon flow rate during the sputtering process of the hydrogen-chromatic thin film to prepare a fluorocarbon / palladium / magnesium-scandium hydrogen-chromatic thin film, and includes the following steps:

[0048] (1) Soak the quartz glass slide in a mixed solution of concentrated sulfuric acid and hydrogen peroxide (volume ratio 3:1), then rinse the quartz glass slide with deionized water; place the cleaned quartz glass slide into the magnetron sputtering reaction chamber, turn on the vacuum system to evacuate to a background vacuum of 3×10⁻⁶. -4 Pa.

[0049] (2) Heat the substrate to a temperature of 20–25°C, introduce working gas A (argon), and maintain a pressure of 0.4–0.6 Pa. After the pressure stabilizes, turn on the power to the palladium, magnesium, and scandium targets, turn off the baffles in front of each target, and pre-sputter clean the targets for 10 min. Then set the co-sputtering process program, with sputtering powers of 40 W and 100 W for the magnesium and scandium targets, respectively, adjusting the argon flow rate to 40 sccm, and the co-sputtering time to 60 s. Begin depositing the magnesium-scandium thin film with a thickness of 50 nm.

[0050] (3) After deposition, under the condition of maintaining a vacuum of 0.5 Pa, the sputtering process of the palladium catalyst layer is loaded, and the sputtering power of the palladium target is adjusted to 80 W, the sputtering time to 14 s, and the film thickness to 5 nm. After the palladium film growth is completed, the power supply of all target materials is turned off, and the sample is continued to be purged with working gas A (argon). Then the sample is taken out to obtain a thin film with the composition of Pd / Mg-Sc.

[0051] (4) The Pd / Mg-Sc thin film was placed in a reactive ion vapor deposition (RIVDC) machine. The process parameters for the fluorocarbon film were set as follows: working gas pressure 4 Pa, working gas (C4F8) flow rate 40 sccm, gas excitation power 600 W, and deposition time 60 s. The working gas was introduced, the process program was loaded, and the fluorocarbon film was deposited to a thickness of 100 nm. After completion, the sample was removed, yielding a CF / Pd / Mg-Sc thin film. The structure of the obtained film is shown below. Figure 1 As shown, it includes a magnesium-scandium composite film layer (Mg-Sc layer), a palladium catalyst layer (Pd layer), and a fluorocarbon film layer (FC layer) sequentially disposed on a substrate.

[0052] A schematic diagram of the transmittance curve of the hydrogen absorption process of the obtained CF / Pd / Mg-Sc thin film is shown below. Figure 2 As shown (the curve represented by 40 sccm), by Figure 2 It can be seen that the hydrogen absorption reaction time of the CF / Pd / Mg-Sc thin film is about 3.5s.

[0053] A schematic diagram of the transmittance curve of the hydrogen desorption process of the obtained CF / Pd / Mg-Sc thin film is shown below. Figure 3 As shown (the curve represented by 40 sccm), by Figure 3 It can be seen that the hydrogen absorption reaction time of the CF / Pd / Mg-Sc thin film is approximately 65.1 s.

[0054] AFM results for CF / Pd / Mg-Sc thin films are as follows: Figure 4 As shown in b, by Figure 4 As can be seen from b, the roughness Rq of the CF / Pd / Mg-Sc thin film is approximately 0.739 nm.

[0055] Comparing Examples 1 and 2, it can be seen that by adjusting the flow rate of argon gas introduced during film sputtering, the roughness of the film can be changed, that is, by affecting the microstructure of the film, the hydrogen absorption and desorption performance of the film can be significantly improved.

[0056] Example 3

[0057] This embodiment provides a method for preparing a hydrogen-chromatic thin film with improved hydrogen adsorption and dehydrogenation response performance. The method involves adjusting the argon flow rate during the sputtering process of the hydrogen-chromatic thin film to prepare a fluorocarbon / palladium / magnesium-scandium hydrogen-chromatic thin film, and includes the following steps:

[0058] (1) Soak the quartz glass slide in a mixed solution of concentrated sulfuric acid and hydrogen peroxide (volume ratio 3:1), then rinse the quartz glass slide with deionized water; place the cleaned quartz glass slide into the magnetron sputtering reaction chamber, turn on the vacuum system to evacuate to a background vacuum of 3×10⁻⁶. -4 Pa.

[0059] (2) Heat the substrate to a temperature of 20–25°C, introduce working gas A (argon), and maintain a pressure of 0.4–0.6 Pa. After the pressure stabilizes, turn on the power to the palladium, magnesium, and scandium targets, turn off the baffles in front of each target, and pre-sputter clean the targets for 10 minutes. Then set the co-sputtering process program, with sputtering powers of 40 W and 100 W for the magnesium and scandium targets, respectively, adjusting the argon flow rate to 60 sccm and the co-sputtering time to 60 s, and begin depositing a magnesium-scandium thin film with a thickness of 50 nm.

[0060] (3) After deposition, under the condition of maintaining a vacuum of 0.5 Pa, the sputtering process of the palladium catalyst layer is loaded, and the sputtering power of the palladium target is adjusted to 80 W, the sputtering time to 14 s, and the film thickness to 5 nm. After the palladium film growth is completed, the power supply of all target materials is turned off, and the sample is continued to be purged with working gas A (argon). Then the sample is taken out to obtain a thin film with the composition of Pd / Mg-Sc.

[0061] (4) The Pd / Mg-Sc thin film was placed in a reactive ion vapor deposition (RIVDC) machine. The process parameters for the fluorocarbon film were set as follows: working gas pressure 4 Pa, working gas (C4F8) flow rate 40 sccm, gas excitation power 600 W, and deposition time 60 s. The working gas was introduced, the process program was loaded, and the fluorocarbon film was deposited to a thickness of 100 nm. After completion, the sample was removed, yielding a CF / Pd / Mg-Sc thin film. The structure of the obtained film is shown below. Figure 1 As shown, it includes a magnesium-scandium composite film layer (Mg-Sc layer), a palladium catalyst layer (Pd layer), and a fluorocarbon film layer (FC layer) sequentially disposed on a substrate.

[0062] A schematic diagram of the transmittance curve of the hydrogen absorption process of the obtained CF / Pd / Mg-Sc thin film is shown below. Figure 2 As shown (the curve represented by 60 sccm), by Figure 2 It can be seen that the hydrogen absorption reaction time of the CF / Pd / Mg-Sc thin film is about 6.1 s.

[0063] A schematic diagram of the transmittance curve of the hydrogen desorption process of the obtained CF / Pd / Mg-Sc thin film is shown below. Figure 3 As shown (the curve represented by 60 sccm).

[0064] Example 4

[0065] This embodiment provides a method for preparing a hydrogen-chromatic thin film with improved hydrogen adsorption and dehydrogenation response performance. The method involves adjusting the argon flow rate during the sputtering process of the hydrogen-chromatic thin film to prepare a fluorocarbon / palladium / magnesium-scandium hydrogen-chromatic thin film, and includes the following steps:

[0066] (1) Soak the quartz glass slide in a mixed solution of concentrated sulfuric acid and hydrogen peroxide (volume ratio 3:1), then rinse the quartz glass slide with deionized water; place the cleaned quartz glass slide into the magnetron sputtering reaction chamber, turn on the vacuum system to evacuate to a background vacuum of 3×10⁻⁶. -4 Pa.

[0067] (2) Heat the substrate to a temperature of 20–25°C, introduce working gas A (argon), and maintain a pressure of 0.4–0.6 Pa. After the pressure stabilizes, turn on the power to the palladium, magnesium, and scandium targets, turn off the baffles in front of each target, and pre-sputter clean the targets for 10 minutes. Then set the co-sputtering process program, with sputtering powers of 40 W and 100 W for the magnesium and scandium targets, respectively, adjusting the argon flow rate to 80 sccm, and the co-sputtering time to 60 s. Begin depositing the magnesium-scandium thin film with a thickness of 50 nm.

[0068] (3) After deposition, under the condition of maintaining a vacuum of 0.5 Pa, the sputtering process of the palladium catalyst layer is loaded, and the sputtering power of the palladium target is adjusted to 80 W, the sputtering time to 14 s, and the film thickness to 5 nm. After the palladium film growth is completed, the power supply of all target materials is turned off, and the sample is continued to be purged with working gas A (argon). Then the sample is taken out to obtain a thin film with the composition of Pd / Mg-Sc.

[0069] (4) The Pd / Mg-Sc thin film was placed in a reactive ion vapor deposition (RIVDC) machine. The process parameters for the fluorocarbon film were set as follows: working gas pressure 4 Pa, working gas (C4F8) flow rate 40 sccm, gas excitation power 600 W, and deposition time 60 s. The working gas was introduced, the process program was loaded, and the fluorocarbon film was deposited to a thickness of 100 nm. After completion, the sample was removed, yielding a CF / Pd / Mg-Sc thin film. The structure of the obtained film is shown below. Figure 1As shown, it includes a magnesium-scandium composite film layer (Mg-Sc layer), a palladium catalyst layer (Pd layer), and a fluorocarbon film layer (FC layer) sequentially disposed on a substrate.

[0070] A schematic diagram of the transmittance curve of the hydrogen absorption process of the obtained CF / Pd / Mg-Sc thin film is shown below. Figure 2 As shown (the curve represented by 80 sccm), by Figure 2 It can be seen that the hydrogen absorption reaction time of the CF / Pd / Mg-Sc thin film is about 4.9 s.

[0071] A schematic diagram of the transmittance curve of the hydrogen desorption process of the obtained CF / Pd / Mg-Sc thin film is shown below. Figure 3 As shown (the curve represented by 80 sccm).

[0072] Example 5

[0073] This embodiment provides a method for preparing a hydrogen-chromatic thin film with improved hydrogen adsorption and dehydrogenation response performance. It is a method for preparing a fluorocarbon / palladium / magnesium-yttrium hydrogen-chromatic thin film by adjusting the argon flow rate during the sputtering process, comprising the following steps:

[0074] (1) Soak the quartz glass slide in a mixed solution of concentrated sulfuric acid and hydrogen peroxide (volume ratio 3:1), then rinse the quartz glass slide with deionized water; place the cleaned quartz glass slide into the magnetron sputtering reaction chamber, turn on the vacuum system to evacuate to a background vacuum of 3×10⁻⁶. -4 Pa.

[0075] (2) Heat the substrate to a temperature of 20–25°C, introduce working gas A (argon), and maintain a pressure of 0.4–0.6 Pa. After the pressure stabilizes, turn on the power to the palladium, magnesium, and yttrium targets, turn off the baffles in front of each target, and pre-sputter clean the targets for 10 minutes. Then set the co-sputtering process program, with sputtering powers of 40 W and 100 W for the magnesium and yttrium targets, respectively, adjusting the argon flow rate to 60 sccm and the co-sputtering time to 60 s, and begin depositing a magnesium-yttrium thin film with a thickness of 50 nm.

[0076] (3) After deposition, under the condition of maintaining a vacuum of 0.5 Pa, the sputtering process of loading palladium catalyst layer is carried out, and the sputtering power of palladium target is adjusted to 80 W, sputtering time to 14 s, and film thickness to 5 nm. After the palladium film growth is completed, the power supply of all target materials is turned off, and the sample is continued to be purged with working gas A (argon). Then the sample is taken out to obtain a thin film with Pd / Mg-Y composition.

[0077] (4) The Pd / Mg-Y thin film was placed in a reactive ion vapor deposition (RIVDC) machine. The process parameters for the fluorocarbon film were set as follows: working gas pressure 4 Pa, working gas (C4F8) flow rate 40 sccm, gas excitation power 600 W, and deposition time 60 s. The working gas was introduced, the process program was loaded, and the fluorocarbon film was deposited to a thickness of 100 nm. After completion, the sample was removed, yielding a CF / Pd / Mg-Sc thin film. The structure of the obtained film is shown below. Figure 1 As shown, it includes a magnesium-scandium composite film layer (Mg-Sc layer), a palladium catalyst layer (Pd layer), and a fluorocarbon film layer (FC layer) sequentially disposed on a substrate.

[0078] The hydrogen absorption reaction time of the CF / Pd / Mg-Y thin film obtained by the test was approximately 5.4 s.

[0079] Example 6

[0080] This embodiment provides a method for preparing a hydrogen-chromatic thin film with improved hydrogen adsorption and dehydrogenation response performance. The method involves adjusting the argon flow rate during the sputtering process of the hydrogen-chromatic thin film to prepare a fluorocarbon / palladium / magnesium-gadolinium hydrogen-chromatic thin film, and includes the following steps:

[0081] (1) Soak the quartz glass slide in a mixed solution of concentrated sulfuric acid and hydrogen peroxide (volume ratio 3:1), then rinse the quartz glass slide with deionized water; place the cleaned quartz glass slide into the magnetron sputtering reaction chamber, turn on the vacuum system to evacuate to a background vacuum of 3×10⁻⁶. -4 Pa.

[0082] (2) Heat the substrate to a temperature of 20–25°C, introduce working gas A (argon), and maintain a pressure of 0.4–0.6 Pa. After the pressure stabilizes, turn on the power to the palladium, magnesium, and gadolinium targets, turn off the baffles in front of each target, and pre-sputter clean the targets for 10 min. Then set the co-sputtering process program, with sputtering powers of 40 W and 100 W for the magnesium and gadolinium targets, respectively, adjusting the argon flow rate to 60 sccm and the co-sputtering time to 60 s, and begin depositing a magnesium-gadolinium thin film with a thickness of 50 nm.

[0083] (3) After deposition, under the condition of maintaining a vacuum of 0.5 Pa, the sputtering process of the palladium catalyst layer is loaded, and the sputtering power of the palladium target is adjusted to 80 W, the sputtering time to 14 s, and the film thickness to 5 nm. After the palladium film growth is completed, the power supply of all target materials is turned off, and the sample is continued to be purged with working gas A (argon). Then the sample is taken out to obtain a thin film with the composition of Pd / Mg-Gd.

[0084] (4) The Pd / Mg-Gd thin film was placed in a reactive ion vapor deposition (RIVDC) machine. The process parameters for the fluorocarbon film were set as follows: working gas pressure 4 Pa, working gas (C4F8) flow rate 40 sccm, gas excitation power 600 W, and deposition time 60 s. The working gas was introduced, the process program was loaded, and the fluorocarbon film was deposited to a thickness of 100 nm. After completion, the sample was removed, yielding a CF / Pd / Mg-Sc thin film. The structure of the obtained film is shown below. Figure 1 As shown, it includes a magnesium-scandium composite film layer (Mg-Sc layer), a palladium catalyst layer (Pd layer), and a fluorocarbon film layer (FC layer) sequentially disposed on a substrate.

[0085] The hydrogen absorption reaction time of the CF / Pd / Mg-Gd thin film obtained by the test was approximately 7.8 s.

[0086] The above description of the embodiments is provided to enable those skilled in the art to understand and use the invention. It will be apparent to those skilled in the art that various modifications can be made to these embodiments, and the general principles described herein can be applied to other embodiments without inventive effort. Therefore, the present invention is not limited to the above embodiments, and any improvements and modifications made by those skilled in the art based on the disclosure of the present invention without departing from the scope of the invention should be within the protection scope of the present invention.

Claims

1. A method for preparing a hydrogen-responsive thin film with improved hydrogen-chromatic properties, characterized in that, The method specifically includes the following steps: S1. Perform surface cleaning pretreatment on the substrate to keep the surface clean and dry; S2. A magnesium-based hydrogen-sensitive reaction layer is deposited on the pretreated substrate using DC magnetron sputtering co-sputtering. During the deposition process, the flow rate of argon gas is controlled to be 40 sccm to adjust the microstructure of the magnesium-based hydrogen-sensitive reaction layer. S3. A catalyst layer is deposited in situ on the magnesium-based hydrogen-sensitive reaction layer by DC magnetron sputtering, so that it inherits the microstructure formed in step S2. S4. A polymer layer is deposited on the catalyst layer using chemical vapor deposition. The magnesium-based hydrogen-sensitive reactive layer is any one of a magnesium-scandium film layer, a magnesium-yttrium film layer, or a magnesium-gadolinium film layer; The catalyst layer is made of Pd.

2. The method for preparing a hydrogen-responsive thin film with improved hydrogen-induced color-changing properties according to claim 1, characterized in that, The thickness of the magnesium-based hydrogen-sensitive reaction layer is 10–100 nm.

3. The method for preparing a hydrogen-responsive thin film with improved hydrogen-induced color-changing properties according to claim 1, characterized in that, In step S2, the target material used is a magnesium target and other element targets; the other element targets are selected from any one of scandium targets, yttrium targets, and gadolinium targets; the sputtering power of the magnesium target is 30-200W, the sputtering power of the other element targets is 40-300W, and the total sputtering time is 30-100s.

4. The method for preparing a hydrogen-responsive thin film with improved hydrogen-induced color-changing properties according to claim 1, characterized in that, In step S3, when depositing the catalyst layer, the sputtering power of the target material is 50-100W and the sputtering time is 10-60s.

5. The method for preparing a hydrogen-responsive thin film with improved hydrogen-induced color-changing properties according to claim 1, characterized in that, In step S4, the material of the polymer layer is selected from any one of fluorocarbon polymers, polymethyl methacrylate, and polytetrafluoroethylene.

6. A hydrogen-chromatic thin film prepared by the method according to any one of claims 1-5.

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