In-situ controllable preparation of ZIF-8-wrapped ZnO heterojunction nanorods array for ppb-level Cl2 detection operated at near room temperature

Real-time monitoring of chlorine gas (Cl2) with a strong irritating odor is an indispensable means of avoiding its contamination of the air and harm to the body. To achieve this purpose, a novel gas-sensitive material capable of detecting low concentrations of Cl2 at near room temperature is developed in this paper. ZIF-8 with a kinetic diameter of 3.4 Å in the designed ZnO@ZIF-8 composites is able to sieve gas molecules with different kinetic diameters, enabling effective improvement of the selectivity of the gas-sensitive materials. In addition, the porous structure of ZIF-8 can provide more reactive sites, which is conducive to improving gas adsorption capacity and providing of channels for gas diffusion. In this study, ZnO@ZIF-8 heterojunction composites are prepared by combining the advantages of ZnO and ZIF-8, which provides a new method for real-time monitoring of low concentrations of Cl2, and also has potential practical applications in fields such as environmental monitoring and industrial safety.