A high-sensitivity air pressure sensor with short desorbing time

Abstract

We proposed and confirmed a highly sensitive gas pressure sensor based on a fiber Mach-Zehnder interferometer, which uses polydimethylsiloxane (PDMS) and metal–organic frameworks (MOF) mixture as gas-sensitive material. PDMS is naturally sensitive to air pressure because its refractive index changes dramatically with the variation of gas pressure. However, due to its small pore size, the gas desorption time is usually long. By introducing MOF with large-size pores and large porosity into PDMS, the multiple channels connected with the outside in PDMS can be established, so that the gas in PMDS can be rapidly desorbed through the channels. Experimental results show that the air pressure sensitivity is 86.7 nm/MPa in the range of 0.08–0.28 Mpa, and the desorption time is shortened to 1/18 of that of pure PDMS.