Zn²⁺-Based Luminescent Metal–Organic Framework for Reversible Sensing of Benzaldehyde and Salicylaldehyde Vapors

Development of highly efficient and rapid detection methods and sensing materials for volatile organic compounds (VOCs) is meaningful in environmental science and chemistry. Herein, a novel Zn2+-based luminescent metal-organic framework with the formula {[(CH3)2NH2][Zn(bidc)]}n (JXUST-56, where JXUST denotes Jiangxi University of Science and Technology) with in situ formed 1H-benzimidazole-4,7-dicarboxylic acid (H3bidc) has been synthesized under solvothermal conditions. JXUST-56 exhibits a characteristic pale blue emission and demonstrates a rapid and selective fluorescence quenching response toward benzaldehyde (BzH) and salicylaldehyde (SA). Notably, the detection limits are as low as 4.10 and 0.259 μM, respectively. Furthermore, to evaluate the practical applicability of JXUST-56, composite film (J-PA) was constructed for sensing BzH and SA vapors, and J-PA exhibits excellent reversible sensing behavior. This work presents an efficient sensing platform and provides valuable insights for the future detection of VOCs.