Preparation of metal–organic framework films by electrophoretic deposition method

• A simple and rapid method of fabrication of MOF thin films based on electrophoretic deposition.
• Different MOFs can be deposited onto different conductive substrates.
• Thin films show good separation properties for hydrogen over carbon dioxide and nitrogen.

Thin HKUST-1 and ZIF-8 films were successfully deposited onto porous stainless steel using an electrophoretic deposition (EPD) method. Both anodic and cathodic EPD methods were tested. Cathodic EPD resulted in the degradation of MOF crystals. This problem was avoided by anodic deposition. SEM and XRD were used to characterize the deposited films. Single gas permeation tests of the HKUST-1 films gave an ideal separation factor up to 4.6 for H2/CO2, and 3.9 for H2/N2.