技术领域technical field
本发明属于气体检测技术领域，具体涉及一种基于卷曲薄膜的氢气痕迹检测方法。The invention belongs to the technical field of gas detection, and in particular relates to a hydrogen trace detection method based on a curled film.
背景技术Background technique
随着社会的发展，工业化程度的加深，能源问题和环境问题受到越来越广泛的关注。一方面，传统化石能源，如石油、煤炭、天然气等不可再生能源消耗加剧，随着人类的不断开采，其枯竭是无法避免的；另一方面，化石能源在使用过程中产生了大量的烟尘，二氧化碳等，带来了雾霾、温室效应等一系列环境问题，威胁着全球的生态环境。因此，开发理想、高效、清洁的新型能源已经成为世界各国的共识。With the development of society and the deepening of industrialization, energy and environmental issues have received more and more extensive attention. On the one hand, the consumption of traditional fossil energy, such as oil, coal, natural gas and other non-renewable energy sources is increasing. With the continuous exploitation of human beings, its exhaustion is unavoidable; Carbon dioxide has brought a series of environmental problems such as smog and greenhouse effect, threatening the global ecological environment. Therefore, the development of ideal, efficient and clean new energy has become the consensus of all countries in the world.
氢能作为一种清洁能源，具有无污染、燃烧热值高、资源丰富等优点。目前，由于电能存在着远程运输损耗大、难以储存等缺点，使得在未来的能源体系中，氢能将取代电能成为各种能量形式之间转化的优良载体。氢能的发展离不开氢气的制备、储运及应用，然而氢气是一种无色无味、易燃易爆的气体，如果氢气在空气中的体积浓度达到4%~75%之间时，遇到火源就会发生爆炸，因此为了提高氢气在制备、储运及应用过程中的安全性，研发高性能的氢气探测和痕迹检测装置已经成为人们日益关注的问题。As a clean energy, hydrogen energy has the advantages of no pollution, high combustion calorific value, and abundant resources. At present, due to the disadvantages of long-distance transportation and difficult storage of electric energy, hydrogen energy will replace electric energy as an excellent carrier for conversion between various energy forms in the future energy system. The development of hydrogen energy is inseparable from the preparation, storage, transportation and application of hydrogen. However, hydrogen is a colorless, odorless, flammable and explosive gas. If the volume concentration of hydrogen in the air reaches between 4% and 75%, It will explode when encountering a fire source. Therefore, in order to improve the safety of hydrogen in the process of preparation, storage, transportation and application, the development of high-performance hydrogen detection and trace detection devices has become an issue of increasing concern.
氢气痕迹检测可以记录氢气泄露的历史情况，检测氢气在使用过程中是否发生过泄露，如在远距离氢气传输管道中的应用，当氢气在传输过程中存在泄露情况时，需要对管道进行排查检修，而氢气痕迹检测技术可以对泄漏位置进行记录，节省检修时间，对工业生产具有重要意义。目前市场上对氢气进行痕迹检测的技术比较少，市场需求广阔。Hydrogen trace detection can record the history of hydrogen leakage and detect whether hydrogen leakage has occurred during use. For example, in the application of long-distance hydrogen transmission pipelines, when hydrogen leakage occurs during the transmission process, the pipeline needs to be checked and repaired. , and the hydrogen trace detection technology can record the leak location, save maintenance time, and is of great significance to industrial production. At present, there are few technologies for trace detection of hydrogen on the market, and the market demand is broad.
发明内容SUMMARY OF THE INVENTION
本发明的目的在于提供一种结构简单、使用方便、安全性好，基于卷曲薄膜的氢气痕迹检测方法。The purpose of the present invention is to provide a hydrogen trace detection method based on a curled film, which is simple in structure, convenient in use and good in safety.
本发明提供的基于卷曲薄膜的氢气痕迹检测方法，其卷曲薄膜为由多层金属薄膜体系卷曲形成的阵列结构；最内层的金属薄膜在氢气气氛中具有体积膨胀效应，卷曲薄膜在接触过氢气之后，其卷曲直径会产生明显的减小，由此导致其光学性质的变化。氢气脱附后卷曲薄膜产生的透射率变化，与氢气浓度具有一定的定量关系，由此可以实现对氢气的痕迹检测。The invention provides a method for detecting hydrogen traces based on a coiled film, wherein the coiled film is an array structure formed by coiling a multilayer metal film system; the innermost metal film has a volume expansion effect in a hydrogen atmosphere, and the coiled film is exposed to hydrogen Afterwards, its crimp diameter will be significantly reduced, resulting in a change in its optical properties. The transmittance change of the curled film after hydrogen desorption has a certain quantitative relationship with the hydrogen concentration, so that the trace detection of hydrogen can be realized.
本发明提供的基于卷曲薄膜的氢气痕迹检测方法，其检测步骤如下：The hydrogen trace detection method provided by the invention based on the curled film, the detection steps are as follows:
(1) 测量通入氢气前卷曲薄膜的透射率a1；(1) Measure the transmittance a1 of the coiled film before passing hydrogen gas;
(2) 将卷曲薄膜置于透明密闭容器中；(2) Place the curled film in a transparent airtight container;
(3) 将氢气通入透明密闭容器中；(3) Pass hydrogen into a transparent airtight container;
(4) 停止通入氢气，将卷曲薄膜置于空气或氮气环境中；(4) Stop the introduction of hydrogen, and place the curled film in an air or nitrogen environment;
(5) 测量通入氢气后卷曲薄膜的透射率a2；(5) Measure the transmittance a2 of the coiled film after passing hydrogen;
(6) 比较通入氢气前后卷曲薄膜的透射率变化a，a = (a2 – a1)/a1；(6) Compare the transmittance change a of the coiled film before and after passing hydrogen, a = (a2 - a1 )/a1 ;
(7) 根据透射率变化率的大小，可以对浓度为0.1%-4%的氢气进行定量痕迹检测。(7) According to the change rate of transmittance, quantitative trace detection can be performed on hydrogen with a concentration of 0.1%-4%.
本发明提供的基于卷曲薄膜的氢气痕迹检测方法，其卷曲薄膜的制备方法如下：The hydrogen trace detection method based on the curly film provided by the present invention, the preparation method of the curly film is as follows:
(1) 在清洁的基片上光刻图形阵列；(1) Photolithography pattern array on clean substrate;
(2) 使用薄膜沉积方法在基片上沉积具有内应力的金属薄膜；(2) depositing a metal film with internal stress on the substrate using a film deposition method;
(3) 使用薄膜沉积方法在基片上沉积对氢气具有体积膨胀效应的金属薄膜；(3) depositing a metal film having a volume expansion effect on hydrogen on the substrate using a film deposition method;
(4) 选择性腐蚀光刻胶得到卷曲薄膜阵列结构。(4) Selectively etching the photoresist to obtain a curled thin film array structure.
本发明中，步骤(1)所述清洁基片为透明玻璃片或石英片的其中一种。In the present invention, the cleaning substrate in step (1) is one of a transparent glass sheet or a quartz sheet.
本发明中，步骤(2)所述具有内应力的金属薄膜为钛、铬、铁、钴、镍、铜、铝的单一组分金属薄膜或是由这些金属中的几种构成的多层金属薄膜结构。In the present invention, the metal film with internal stress described in step (2) is a single-component metal film of titanium, chromium, iron, cobalt, nickel, copper, and aluminum or a multi-layer metal composed of several of these metals. thin film structure.
本发明中，步骤(3)所述对氢气具有体积膨胀效应的金属薄膜为钯、铂的单一组分金属薄膜或是含有这些金属组分的合金薄膜。In the present invention, the metal film having a volume expansion effect on hydrogen described in step (3) is a single-component metal film of palladium and platinum or an alloy film containing these metal components.
本发明中，步骤(2)-(3)所使用的薄膜沉积方法是指电子束蒸发沉积、热蒸发沉积、激光脉冲沉积或磁控溅射等方法的其中一种。In the present invention, the thin film deposition method used in steps (2)-(3) refers to one of the methods such as electron beam evaporation deposition, thermal evaporation deposition, laser pulse deposition or magnetron sputtering.
本发明中，步骤(2)-(3)所述的金属薄膜的厚度为10-200纳米。In the present invention, the thickness of the metal thin film described in steps (2)-(3) is 10-200 nanometers.
有益效果：本发明提供了一种基于卷曲薄膜的氢气痕迹检测方法，实现了无需其他附加设备的氢气历史留痕检测，可以记录氢气泄露的历史情况并将结果直观反映出来。本发明在检测和记录过程中没有电流传输，因而在氢气环境中更加安全，使用更加方便。本发明所提供的制备方法简单，可适用于工业生产中，具有实际应用意义。Beneficial effects: The present invention provides a method for detecting hydrogen traces based on a curly film, which realizes the detection of historical traces of hydrogen without other additional equipment, and can record the historical situation of hydrogen leakage and directly reflect the results. The present invention has no current transmission in the process of detection and recording, so it is safer in a hydrogen environment and more convenient to use. The preparation method provided by the invention is simple, can be applied to industrial production, and has practical application significance.
本发明的独创性在于利用卷曲薄膜阵列结构，在内层沉积对氢气具有体积膨胀效应的金属薄膜，通过氢气脱附后卷曲薄膜产生的透射率变化，与氢气浓度具有一定的定量关系，实现对氢气的痕迹检测。The originality of the invention lies in the use of the coiled film array structure to deposit a metal film with a volume expansion effect on hydrogen in the inner layer, and the transmittance change generated by the coiled film after desorption of hydrogen has a certain quantitative relationship with the hydrogen concentration. Trace detection of hydrogen gas.
附图说明Description of drawings
图1为基于卷曲薄膜氢气痕迹检测的工作原理图。(a)为通入氢气前的3×3卷曲薄膜阵列，(b)为通入氢气前的单一卷曲薄膜侧视图，(c)为通入氢气后的3×3卷曲薄膜阵列，(d)为通入氢气后的单一卷曲薄膜侧视图。其中阴影部分为透光区域。Figure 1 is a schematic diagram of the working principle of hydrogen trace detection based on curled films. (a) is a 3×3 coiled film array before hydrogen is introduced, (b) is a side view of a single coiled film before hydrogen is introduced, (c) is a 3×3 coiled film array after hydrogen is introduced, (d) This is a side view of a single rolled film after hydrogen gas is introduced. The shaded part is the light-transmitting area.
图中标号：1-基片；2-具有内应力的金属薄膜；3-对氢气具有体积膨胀效应的金属薄膜；4-光线。Symbols in the figure: 1-substrate; 2-metal film with internal stress; 3-metal film with volume expansion effect on hydrogen; 4-light.
图2为通入2%浓度氢气前后的卷曲薄膜阵列图：(a)为通入2%浓度氢气前的卷曲薄膜阵列，(b)为通入2%浓度氢气后的卷曲薄膜阵列。Figure 2 is a picture of the coiled film array before and after the introduction of 2% hydrogen concentration: (a) is the coiled film array before the introduction of 2% hydrogen concentration, (b) is the coiled film array after the introduction of 2% concentration hydrogen.
图3为通入2%浓度氢气前后卷曲薄膜阵列的透射率变化图。Figure 3 is a graph showing the change in transmittance of the coiled film array before and after the introduction of 2% hydrogen concentration.
图4为通入4%浓度氢气前后卷曲薄膜阵列的透射率变化图。Figure 4 is a graph showing the change in transmittance of the coiled film array before and after the introduction of 4% hydrogen concentration.
具体实施方式Detailed ways
以下将结合附图，以钛、铬双层内应力金属薄膜-钯金属薄膜组成的卷曲薄膜体系为例详细说明其制备方法及应用效果。以下实施例用于说明本发明，但不作为对本发明内容的限制。The preparation method and application effect thereof will be described in detail below with reference to the accompanying drawings, taking the coiled film system composed of titanium and chromium double-layer internal stress metal film-palladium metal film as an example. The following examples are used to illustrate the present invention, but are not intended to limit the content of the present invention.
实施例1Example 1
(1) 取1 cm×1 cm的玻璃片作为基片，用丙酮、乙醇、去离子水依次进行超声清洗十分钟，然后在氮气流中干燥。(1) Take a 1 cm × 1 cm glass plate as a substrate, ultrasonically clean it with acetone, ethanol, and deionized water for ten minutes in sequence, and then dry it in a nitrogen stream.
(2) 使用中国鑫有研公司的KW-4A型匀胶机在基片表面旋涂一层光刻胶。光刻胶型号为德国Allresist公司的AR-P3510T正性光刻胶。低转速为600 rpm，旋转时间为6 s；高转速为4000 rpm，旋转时间为30 s。然后置于电热板上在90 ℃下前烘90 s。使用德国Heidelberg Instruments公司的μPG501激光直写光刻机光刻阵列。将光刻后的基片浸没于苏州瑞红电子化学品有限公司RZX-3038型正胶显影液中25 s后用去离子水清洗，经氮气流干燥后得到光刻基片。(2) A layer of photoresist was spin-coated on the surface of the substrate using the KW-4A type glue dispenser of China Xinyouyan Company. The photoresist model is AR-P3510T positive photoresist from Allresist, Germany. The low speed was 600 rpm and the spin time was 6 s; the high speed was 4000 rpm and the spin time was 30 s. It was then placed on a hot plate and pre-baked at 90 °C for 90 s. The arrays were lithographed using a μPG501 laser direct writing lithography machine from Heidelberg Instruments, Germany. The photolithographic substrate was immersed in RZX-3038 positive-resist developer of Suzhou Ruihong Electronic Chemicals Co., Ltd. for 25 s, washed with deionized water, and dried in a nitrogen stream to obtain a photolithographic substrate.
(3) 使用深圳天星达公司TSV700型电子束蒸发镀膜机进行金属薄膜的电子束蒸发沉积。将基片倾斜固定于样品架上，倾斜角度为60°，使得蒸发材料倾斜沉积于基片上。首先蒸发具有内应力的金属薄膜：以1 Å/s的速率沉积10 nm钛金属，再以1 Å/s的速率沉积10nm铬金属。然后蒸发对氢气具有体积膨胀效应的金属薄膜：以1 Å/s的速率沉积80 nm钯金属。(3) Electron beam evaporation deposition of metal thin films was carried out using TSV700 electron beam evaporation coating machine from Shenzhen Tianxingda Company. The substrate was fixed on the sample holder obliquely, and the inclination angle was 60°, so that the evaporation material was obliquely deposited on the substrate. Metal films with internal stress are first evaporated: 10 nm of titanium metal is deposited at a rate of 1 Å/s, followed by 10 nm of chromium metal at a rate of 1 Å/s. Metal films with a volume expansion effect on hydrogen were then evaporated: 80 nm of palladium metal was deposited at a rate of 1 Å/s.
(4) 使用美国Tousimis公司的Autosamdri-815B Series B型超临界干燥仪对牺牲层进行选择性腐蚀。将样品放置于超临界干燥仪的腔体内，向腔体内倒入适量丙酮溶解光刻胶，然后进行超临界干燥。待干燥程序结束后取出样品，得到由钛、铬、钯金属薄膜体系组成的卷曲薄膜阵列（图1(a)），单一卷曲薄膜的侧视图（图1(b)）。(4) Use the Autosamdri-815B Series B type supercritical dryer from Tousimis, USA to selectively etch the sacrificial layer. Place the sample in the cavity of the supercritical dryer, pour an appropriate amount of acetone into the cavity to dissolve the photoresist, and then perform supercritical drying. After the drying procedure, the sample was taken out to obtain a coiled film array composed of titanium, chromium, and palladium metal film systems (Fig. 1(a)), and a side view of a single coiled film (Fig. 1(b)).
(5) 响应测试：将样品置于透明密闭容器中，向容器内通入一定体积分数的氢气后撤去氢气，将样品置于空气或氮气环境中，卷曲薄膜的曲率半径减小，卷曲程度增大（图1(c)和图1(d)）。使用日本岛津仪器公司的UV-2550紫外可见分光光度计测量通入氢气前后卷曲薄膜的透射率变化。将薄膜恢复卷曲后产生的透射率变化作为氢气痕迹检测的记录。(5) Response test: place the sample in a transparent airtight container, pass a certain volume fraction of hydrogen into the container, then remove the hydrogen, and place the sample in an air or nitrogen environment, the radius of curvature of the curled film decreases and the degree of curling increases large (Fig. 1(c) and Fig. 1(d)). The transmittance changes of the coiled films before and after hydrogen gas were measured using a UV-2550 UV-Vis spectrophotometer from Shimadzu Instruments, Japan. The change in transmittance after the film was re-curled was recorded as hydrogen trace detection.
(6) 图2为通入2%浓度氢气前后的卷曲薄膜阵列，其透射率变化如图3所示，通入氢气前透射率平均值为50.7%，通入氢气后透射率平均值为52.4%，其透射率变化率为3.4%。(6) Figure 2 shows the coiled film array before and after the introduction of 2% hydrogen concentration. The change in transmittance is shown in Figure 3. The average transmittance before the introduction of hydrogen is 50.7%, and the average transmittance after the introduction of hydrogen is 52.4 %, the transmittance change rate is 3.4%.
实施例2Example 2
与实施例1的制备及测试方法相同，图4为通入4%浓度氢气前后的卷曲薄膜阵列，其透射率变化如图5所示，通入氢气前透射率平均值为49.6%，通入氢气后透射率平均值为52.0%，其透射率变化率为4.8%。经过不同浓度的氢气响应，薄膜卷曲程度随着氢气浓度的增大而增大，其透射率变化值相应增大。The preparation and testing methods are the same as those of Example 1. Figure 4 shows the coiled film array before and after the introduction of 4% hydrogen concentration. The change in transmittance is shown in Figure 5. The average transmittance after hydrogen is 52.0%, and the transmittance change rate is 4.8%. After the response of different concentrations of hydrogen, the curling degree of the film increases with the increase of hydrogen concentration, and the change value of its transmittance increases correspondingly.
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| CN201910776964.8ACN110455751A (en) | 2019-08-22 | 2019-08-22 | A kind of hydrogen trace detection method based on curled film |
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| CN201910776964.8ACN110455751A (en) | 2019-08-22 | 2019-08-22 | A kind of hydrogen trace detection method based on curled film |
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| CN201910776964.8APendingCN110455751A (en) | 2019-08-22 | 2019-08-22 | A kind of hydrogen trace detection method based on curled film |
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| WD01 | Invention patent application deemed withdrawn after publication | Application publication date:20191115 |