Barium titanate nanoparticle based nonlinear optical humidity sensor
Year: 2018
Journal: Sens. Actuator B-Chem., Volume 273, NOV 10, page 921–926
Authors: Reynolds, Aaron J.; Conboy, John C.
Organizations: National Science Foundation [1402901]
Keywords: Second harmonic generation; Humidity sensor; Barium titanate
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.
