Ultra-Sensitive and Broad Range Phononic-Fluidic Cavity Sensor for Determination of Mass Fractions in Aqueous Solutions

摘要

This paper presents a 3D-printed phononic-fluidic cavity sensor to measure volumetric physical properties of a liquid. This device features a new type of acoustic fluid sensor with very high, linear sensitivity in a very broad concentration range, solid-air 3D phononic crystal layers confining a fluidic cavity resonator to generate a strong, well separated cavity resonance within the phononic band gap, and ultra-sensitive determination of sodium chloride and glucose concentrations in aqueous solutions. For NaCl solutions in a device with a cavity resonance around 200 kHz we measure a sensitivity of 1.4 kHz / % resulting in a high resolution of 350 ppm over a concentration range of 0% – 23%.