A second harmonic generation humidity sensor was constructed with a sensing layer composed of cubic phase barium titanate nanoparticles. The sensor shows a linear response up to a relative humidity of 80%, with response times of 40 ± 10 s for decreasing, and 39 ± 7 s for increasing humidity. The mechanism of humidity sensitivity is attributed to the modulation of interfacial electric fields due to water vapor adsorption. This research represents the first attempt to bring the surface sensitivity of second harmonic generation to bear on the issue of humidity sensing.

中文翻译：

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基于钛酸钡纳米粒子的非线性光学湿度传感器

使用由立方相钛酸钡纳米粒子组成的传感层构造二次谐波湿度传感器。传感器显示出高达80％的相对湿度的线性响应，响应时间的减少时间为40±10 s，湿度增加的时间为39±7 s。湿度敏感性的机理归因于水蒸气吸附引起的界面电场的调制。这项研究代表了使二次谐波的表面灵敏度适应湿度感测问题的首次尝试。