Thermotropic schiff-base liquid crystal as an LB thin-film material for SPR-based VOC detection: synthesis, characterization and sensor performance
Journal of Materials Science: Materials in Electronics, cilt.37, sa.27, 2026 (SCI-Expanded, Scopus)
- Yayın Türü: Makale / Tam Makale
- Cilt numarası: 37 Sayı: 27
- Basım Tarihi: 2026
- Doi Numarası: 10.1007/s10854-026-18549-2
- Dergi Adı: Journal of Materials Science: Materials in Electronics
- Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Aerospace Database, Applied Science & Technology Source, Chemical Abstracts Core, Compendex, INSPEC, MEDLINE, Engineering Source (EBSCO), Materials Science & Engineering Collection (ProQuest), Technology Collection (ProQuest)
- Uşak Üniversitesi Adresli: Evet
Özet
In this study, a new thermotropic liquid crystal Schiff base (LCSB) was synthesized and used as an active sensing material for surface plasmon resonance (SPR)-based VOC detection. The synthesized LCSB was structurally characterized by FT-IR, 1H-NMR, 13C-NMR, mass spectrometry, and elemental analysis, while its thermal and mesomorphic properties were investigated using differential scanning calorimetry and polarized optical microscopy. The results confirmed that the synthesized compound exhibits an enantiotropic smectic C (SmC) mesophase. Langmuir–Blodgett (LB) thin films was fabricated efficiently and reproducibly at an optimum surface pressure of 18 mN m−1 with an average transfer ratio of 94.98%. UV–Vis spectroscopy confirmed the optical absorption of the films, and the absorbance increased linearly with the number of deposited layers, indicating the formation of homogeneous multilayer films. The fabricated SPR sensor was evaluated towards dichloromethane, chloroform, benzene, and toluene vapors. The highest sensitivity of 0.0725 × 10⁻3 ppm⁻1 was obtained for chloroform, whereas sensitivities of 0.0660 × 10−3, 0.0511 × 10−3, and 0.0406 × 10−3 ppm−1 were achieved for benzene, dichloromethane, and toluene, respectively. The sensor exhibited rapid response times of 1–3 s and recovery times ranging from 10 to 20 s, with limits of detection between 45.52 and 81.28 ppm and correlation coefficients (R2) of 0.959–0.978. The results demonstrate that the investigated thermotropic Schiff-base derivative can form reproducible LB thin films and provide rapid room-temperature SPR responses toward the investigated VOCs.