Polyhedral zeolitic imidazolate frameworks three-dimensional photonic crystals for highly sensitive chlorinated vapors sensing

Chlorinated vapors, as one of the poisonous volatile organic compounds (VOCs), seriously pollute the environment and threaten human health. It still remains a major challenge for designing reliable chlorinated vapors sensing materials with high sensitivity. Herein, we propose a simple yet powerful optical sensor based on zeolitic imidazolate frameworks ZIF-8 three-dimensional photonic crystals (3D PCs), which keeps high efficiency in vapor sensing through varying their effective refractive index (RI). ZIF-8 3D PCs sensors with tunable crystal facets and photonic bandgap were prepared by self-assembly of monodisperse polyhedral ZIF-8 particles, which are truncated rhombic dodecahedral (TRD)-, rhombic dodecahedral (RD)-, truncated cubic (TC)-, and spherical (Sphere) ZIF-8 3D PCs sensors. The application of polyhedral ZIF-8 3D PCs sensors for chlorinated vapors detection was investigated. The selectivity was found to be closely related to the exposed crystal facets, and the TRD ZIF-8 3D PCs sensor exhibited excellent selectivity, sensitivity (0.514 nm ppm−1), and sensing performance for chlorobenzene (C6H5Cl) vapor, the ultrafast response time (≤1 s) and remarkable long-term stability and recyclability, which might ultimately benefit for practical VOCs sensing applications.