Optical fiber hydrogen (H2) sensors have garnered attention for avoiding explosion hazards in flammable gas environments. Conventional optical fiber sensors rely on electron beam sputtering and chemical coating for functionalization, but these methods may not achieve precise functionalization of intricate structures. Based on 4D printing principles, an H2‐sensitive ink containing methacrylate groups modified palladium (Pd) nanoparticles (NPs) is reported, with a printing resolution of 200 nm. Then, a fiber‐tip clamped‐beam H2 sensor is fabricated with the femtosecond (Fs) laser‐induced two‐photon polymerization (TPP) technique. The sensor exhibits compact dimensions and fast responses, only 2.64 s for a 4.0 vol.% H2 concentration. A high sensitivity of roughly 165 pm %−1 is achieved as the H2 concentration increases from 0% to 5.5 vol.%. This study demonstrates that H2‐sensitive microstructures can be flexibly achieved by TPP of H2‐sensitive inks, offering a solution for achieving on‐chip direct laser writing of integrated H2 microsensors.

中文翻译：

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使用 Fiber-Tip 氢微传感器的 4D 打印氢敏油墨


光纤氢气 （H2） 传感器因在易燃气体环境中避免爆炸危险而受到关注。传统的光纤传感器依靠电子束溅射和化学涂层进行功能化，但这些方法可能无法实现复杂结构的精确功能化。基于 4D 打印原理，报道了一种含有甲基丙烯酸酯基团改性钯 （Pd） 纳米颗粒 （NPs） 的 H2 敏感墨水，打印分辨率为 200 nm。然后，使用飞秒 （Fs） 激光诱导双光子聚合 （TPP） 技术制造光纤尖端夹紧光束 H2 传感器。该传感器尺寸紧凑，响应速度快，对于 4.0 vol.% H2 浓度，只需 2.64 秒。当 H2 浓度从 0% 增加到 5.5 vol.% 时，可实现大约 165 pm %-1 的高灵敏度。这项研究表明，H2 敏感墨水的 TPP 可以灵活地实现 H2 敏感微结构，为实现集成 H2 微传感器的片上直接激光写入提供了一种解决方案。