Metal-organic frameworks (MOFs) have been attracting intensive attention because of their commendable potential in many applications. Postsynthetic modification for redesigning chemical characteristics and pore structures can greatly improve performance and expand functionality of MOF materials. Here, we develop a versatile vapor-phase linker exchange (VPLE) methodology for MOF modification. Through solvent-free and environment-friendly VPLE processing, various linker analogs with functional groups but not for straightforward MOF crystallization are inserted into frameworks as daughter building blocks. Besides single exchange for preparing MOFs with dual linkers, VPLE can further be performed by multistage operations to obtain MOF materials with multiple linkers and functional groups. The halogen-incorporated ZIFs exhibit good porosity, tunable molecular affinity, and impressive CO2/N2 and CH4/N2 adsorption selectivities up to 31.1 and 10.8, respectively, which are two to six times higher than those of conventional adsorbents. Moreover, VPLE can substantially enhance the compatibility of MOFs and polymers.

In this study, we report a novel air–water interfacial self‐crystallization (AWISC) method for scalable depositing continuous metal–organic framework (MOF) layers on modification‐free polyvinylidene fluoride (PVDF) hollow fibers. Through importing MOF precursors into porous hollow fiber substrates with outer diameters of 1.2 mm and evaporating aqueous solutions under mild conditions, the metal ions and linkers close to solution surface can be concentrated firstly, thus the crystallization of MOFs will preferentially occur at interface of air and liquid precursors. The formed crystals can block off the pores of substrates to form defect‐free MOF membranes. The prepared ZIF‐8 membranes exhibit superior performance in molecular separation, with high rejections of 94.1 ∼ 99.5% for small molecules (molecular weight: 320 ∼ 800 Da) and large permeance up to 50 L m−2 h−1 bar−1. Moreover, by combining AWISC and microfluidic processing, the high‐performance ZIF‐8 hollow fiber membranes with long length of 30 cm can be easily fabricated in scalability.

Metal-organic framework (MOF) membranes are promising for efficient separation applications. However, the uncontrollable pathways at atomic level impede the further development of these membranes for molecular separation. Herein we show that vapor linker exchange can induce partial amorphization of MOF membranes and then reduce their transport pathways for precisely molecular sieving. Through exchanging MOF linkers by incoming ones with similar topology but higher acidity, the resulted metal-linker bonds with lower strength cause the transformation of MOF membranes from order to disorder/amorphous. The linker exchange and partial amorphization can narrow intrinsic apertures and conglutinate grain boundary/crack defects of membranes. Because of the formation of ultra-microporous amorphous phase, the MOF composite membrane shows competitive H 2 /CO 2 selectivity up to 2400, which is about two orders of magnitude higher than that of conventional MOF membranes, accompanied by high H 2 permeance of 13.4 Â 10 À8 mol m À2 s À1 Pa À1 and good reproducibility and stability.

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Solvent-free chemical vapor crosslinking is reported for controlling the interlayer spacing of graphene oxide (GO) membranes by nucleophilic substitution and condensation reactions between GO and ethylenediamine (EDA) vapor. The prepared...