A UiO-66 3D photonic crystal optical sensor for highly efficient chlorobenzene vapor detection.

Chlorobenzene (CHCl) is a flammable liquid with high vapor activity, which is a severe threat to the environment and human health. Therefore, it is essential to develop a highly efficient sensor to detect CHCl vapor. Herein, we developed a UiO-66 three-dimensional photonic crystal (3D PC) optical sensor and investigated its sensing properties toward the CHCl vapor. The UiO-66 3D PCs optical sensor shows a high sensitivity of CHCl vapor, in the concentrations range of 0-500 ppm, the reflectance intensity response to be 0.06% ppm with a good linear relationship, detection limit can reach 1.64 ppm and the quality factor is 10.8. Additionally, the UiO-66 3D PC optical sensor demonstrated great selectivity with the values of selectivity () varying from 2.24 to 10.65 for the CHCl vapor as compared with carbon tetrachloride (CCl), dichloromethane (CHCl), 1,1,2-trichloroethane (CHCl), benzene (CH), deionized water (HO), ethanol (CHOH) and methyl alcohol (CHOH) vapors. Moreover, the UiO-66 3D PC optical sensor shows an ultrafast optical response time and recovery times of 0.5 s and 0.45 s with exceptional stability and repeatability to 500 ppm CHCl vapor. These excellent sensing properties are attributed to the efficacy of signal transduction, increased porosity and gas adsorption sites, which are intrinsically endowed by the design of the 3D optical structure. The design and fabrication of this UiO-66 3D PC optical sensor might open up potential applications for the detection of the CHCl vapor.