Palladium‐polymer bilayer on a soft substrate for optical hydrogen sensing
Palladium‐polymer bilayer on a soft substrate for optical hydrogen sensing
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用于光学氢传感的软基底上的钯聚合物双层
DOI：
10.1002/nano.202100198
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发表时间：
2021
期刊：
影响因子：
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通讯作者：
Chongjun Jin
中科院分区：
文献类型：
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作者：
Xiaoyi She;Qiankun Yao;Guowei Yang;Yang Shen;Chongjun Jin
由于氢气(H2)的易燃性，检测空气中的氢气是必不可少的。光学氢气传感器比电子式氢气传感器更安全，因为它可以通过远程读出消除潜在的火花风险。钯基光学氢传感器引起了人们的广泛关注。然而，敏感材料的杂质中毒是制约氢敏传感器应用的一个严重问题。在这里，我们报告了在聚二甲基硅氧烷(PDMS)衬底上的钯(Pd)-PMMA双层膜可以消除空气中杂质(如氧气)的不利影响。在Pd表面涂覆一层16 nm的PMMA膜后，在4%H_2中加入干空气后，25 nm Pd膜的氢化时间可缩短到5秒。同时，PDMS上的Pd-PMMA双层膜在整个可见光波段有22.7%的高反射率变化，反射率对比度超过370%，这是由于在氢化过程中PDMS上的Pd膜的体积膨胀在皱折表面产生的光散射所致。通过在600 nm波长上设置反射率变化4%的报警阈值，传感器的响应时间可以缩短到1秒。这种光学氢气传感器具有成本低、操作简单、光学对比度高、响应速度快等特点，具有很大的实际应用潜力。
The detection of hydrogen in air is essential because of the flammability of hydrogen gas (H2). Optical hydrogen sensor is safer than electrical hydrogen sensor because it can eliminate the potential risk of sparks by reading out remotely. Palladium‐based optical hydrogen sensors have attracted lots of attentions. However, impurity poisoning of the sensing materials is a severe problem for the utilization of hydrogen sensors. Here, we report that a palladium (Pd) ‐PMMA bilayer on a polydimethylsiloxane (PDMS) substrate can eliminate the adverse effect of the impurity (such as oxygen) in air. With a 16‐nm PMMA layer coating on the Pd surface, the hydrogenation time of a 25‐nm Pd film on PDMS can decrease to 5 seconds exposed to 4% H2mixed with dry air. Meanwhile, the Pd‐PMMA bilayer on PDMS shows a high reflectance change over 22.7% at the whole visible band with the reflectance contrast more than 370% due to the light scattering on the wrinkling surface induced by the volume expansion of the Pd film on PDMS during hydrogenation. By setting the alarm threshold of the reflectance change of 4% at the 600‐nm wavelength, the response time of the sensor can be reduced to 1 second. This optical hydrogen sensor is low‐cost and easy‐operation with high optical contrast and fast response rate, showing great potential for practical applications.