A room temperature acetone sensor based on synthesized tetranitro-oxacalix[4]arenes: Thin film fabrication and sensing properties

Abstract

Tetranitro-oxacalix[4]arenes were prepared to determine their thin film fabrication and gas sensing applications. Firstly, tetranitro-oxacalix[4]arenes (1-3) were synthesized via nucleophilic aromatic substitution reaction (SNAr) using substituted resorcinol derivatives and 1,5-difluoro-2,4-dinitrobenzene with moderate to high yields. Later, successfully synthesized materials were utilized to construct thin films using the spin coating method and the characterization of the deposited films was performed with UV–vis and surface plasmon resonance (SPR). Characterization results indicated that high-quality spin-coated thin films were prepared using these materials. The sensing abilities of the spin-coated thin films of tetranitro-oxacalix[4]arenes (1-3) were tested using the SPR method for volatile organic vapours of acetone, chloroform, toluene, ethanol and benzene. High concentration sensitivity values of 0.0700 × 10−3, 0.1001 × 10−3 and 0.8653 × 10−3 with normalized response/ppm unit for acetone vapour were obtained for thin films (1-3), respectively. The sensors obtained using especially thin films 1 and 3 showed high responses toward acetone even at low concentration ranges between 3.8–15.2 ppm. These sensors have the advantages of high sensitivity, reusability and reproducibility of results which make them compatible for practical acetone-detection applications.