Development of roll- to-roll coated ZIF-67-Modified on PET as an emerging encapsulant for photovoltaics

Polyethylene terephthalate (PET) substrates were modified with a metal-organic framework for the fabrication of an encapsulant film. Zeolitic imidazolium framework was dispersed in a polyvinyl alcohol matrix which was then used for the roll-to-roll coating over the PET sheet. The moisture barrier properties were evaluated using cavity ring-down spectroscopy. The water vapor transmission rate obtained per meter square area per day was lower compared to the reference PET. About forty-five times improvement in the moisture barrier and excellent optical transmittance properties were observed for the post-modified Zeolitic imidazolium framework on PET.