Freestanding ZIF-8 Membrane in Microfluidic Channel

Freestanding ZIF-8 membrane in microfluidic channel

 

Tsz Nok Ng¹, Kailin He¹, King Lun Yeung^1,2,*

¹Department of Chemical and Biomolecular Engineering, ²Division of Environment, ³Nano Science and Technology Program, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, P.R. China

*Corresponding author: kekyeung@ust.hk

Abstract:

 Zeolitic imidazolate frameworks (ZIFs) are metal-organic frameworks (MOFs) that consist of metal centers connected by organic imidazole linkers. The zeolitic networks of pores give the material a rich topological and chemical diversity. ZIFs have potential applications in chemical conversion, separation and storage as well as in sensing, electronics and medicine. Freestanding ZIF-8, and ZIF-67 micromembranes were fabricated within the confined space of the glass microchannels. This is achieved by establishing two parallel flows of reactants within the channel and inducing nucleation, crystallization and growth at the flow interface. In addition, due to the common organic imidazole linkers (2-methylimidazole) shared among ZIF-67 and ZIF-8, the membranes can be prepared simultaneously using three parallel flow streams in a single microchannel. Microfluidic environment allows stable laminar flow to be generated, creating opportunities to generate parallel streams. A single membrane can be prepared with two parallel streams. By adding one more stream, two different membranes can be prepared simultaneously.