Enhanced humidity sensing performance of LiF-doped MgTiO₃ ceramics via spark plasma sintering

The fabrication of low-porosity ceramics for humidity sensing is crucial to prevent moisture entrapment, which poses significant challenges. Using Spark Plasma Sintering (SPS), we successfully densified fine-grained ceramic materials based on LiF-doped MgTiO₃, comparing them with conventionally sintered counterparts. Structural and microstructural analyses, employing X-ray diffraction and Scanning Electron Microscopy (SEM), were conducted. Investigation into electrical and dielectric properties' variations concerning humidity levels was conducted and revealed that SPS sintered ceramics exhibit heightened sensitivity to moisture, as evidenced by resistivity, capacitance, and response time measurements. The implications of these results are discussed in depth, highlighting the potential of SPS as a promising method for fabricating humidity sensors with improved performance and reduced porosity-related issues.