Green synthesis of a hydrophobic metal-organic gel for the capture of trace odorous hexanal from humid air

The development of superhydrophobic adsorbents for the capture of trace volatile organic compounds (VOCs) from humid indoor air is still a challenge. Herein, we reported the formation of a granular zinc-based metalorganic gel, i.e., ZIF-412(gel) by optimizing the synthesis conditions. The thermally stable xerogel exhibited high surface area (1008 m(2)/g), hydrophobicity, and viscosity for self-depositing on the substrate such as non-woven fibers. Dynamic adsorption experiments under various humidity conditions demonstrated as-synthesized ZIF-412 (gel) owned excellent VOC (hexanal) adsorption performance with adsorption capacity higher than commercial activated carbon and some water-stable MOFs including ZIF-8, ZIF-67, MIL-101(Cr) and ZIF-414. ZIF-412(gel) could be regenerated at temperature as low as 358 K without obvious loss in adsorption capacity. The adsorption mechanism of hexanal over ZIF-412(gel) is also simulated by Grand canonical Monte Carlo (GCMC).

Automated summary

In this study, a granular zinc-based metalorganic gel, ZIF-412(gel), was synthesized and found to exhibit excellent adsorption performance for capturing trace volatile organic compounds. Compared to commercial activated carbon and other MOFs, ZIF-412(gel) showed higher adsorption capacity and could be regenerated at a low temperature without significant loss in capacity.