| Metal-organic Frameworks(MOFs)are one of the fastest-growing materials in the application studies of adsorption,separation,catalysis,energy,etc.,due to their unique features,such as high porosity,large surface area,and excellent thermal stability.However,the insoluble and non-meltable nature of MOFs leads to difficulties in handling and processing.In addition,the microporous structure of most reported MOFs limits molecular diffusion and mass transfer,further hindering their practical applications.In this regard,integrating MOFs with polymers is an attractive solution to address these challenges,since low cost polymers sufficiently improve the processability of pure MOFs.Whereas,the fabrication methods of composites still suffer from poor compatibility between MOFs and polymers,non-unifoxm dispersion of MOFs in the composite,as well as tedious manufacturing processes.Therefore,the development of an efficient and effective fabrication strategy to construct MOF/polymer porous composites is highly desirable and attractive.In this work,we present a novel one-pot fabrication strategy to directly prepare MOF/polymer composite from a homogeneous stock solution containing MOF precursors and polymer.It is worth mentioning that this one-pot strategy not only alleviated the MOF aggregation and sedimentation problem since it started from a uniform mixture of MOF precursors and polymer,but also eliminated the need to prepare and disperse MOF particles separately since the growth of MOFs occurred during the fabrication process.Besides,the introduction of macropores or mesopores also accelerated mass transfer of guest molecules in the composite.The main conclusions are as follows.(1)MOF/polymer composite bead was prepared via a "one-pot" phase inversion strategy.Combining macropores introduced by phase inversion and micropores owned by MOF,the ZIF-8/PAN compsite beads possessed a macro-micro hierarchically porous structure.The composite showed a fast benzotriazole adsorption from water,having an adsorption rate of 3.17×10-4 g mg-1 min-1(9.3 times higher than that of the pristine ZIF-8).(2)MOF/polymer composite monolith was prepared via a "one-pot" solvent crystal templated strategy.The solvent crystal template introduced interconnected macropores in the polymer matrix.Combining with microporous structure of MOFs,the obtained ZIF-8/polyurethane(PU)pocessed a hierarchically porous structure.The composite exhibited an accelerated lemon yellow adsorption rate constant of 1.89×10-3 g mg-1 min-1,which was 2.6 times higher than that of MOF powders.In addition,the composite showed good compression properties and recyclability.(3)MOF/polymer composite was prepared via a "one-pot" solvent evaporation stragety.During the evaporation process,the interaction between MOF and polymer led to the formation of macropores in the polymer matrix and mesopores in the MOF crystals and polymer,thus endowing the HKUST-1/polyvinylidene fluoride(PVDF)composite with a hierarchically macro-meso-micro porous structure.This "all-in-one"porous structure could enhance the mass transport property of molecules within the composite,which showed an enhanced CO2 adsorption rate constant of 0.821 min-1(3.5 times higher than that of the pristine HKUST-1)and an equivalent gas adsorption capacity of 1.47 mmol g-1.(4)MOF/polymer composite nanofibrous membrane was prepared via a "one-pot"electrospnning strategy.The composite membranes were used as separators in Li-metal full batteries under harsh testing conditions,using an ultrathin Li-metal anode and a high mass loading cathode.The results demonstrated significantly improved cycling performance(capacity retention of 83.1%after 200 cycles)compared with commercial polypropylene(PP)separator and pure PAN fiber separator.The improvement can be attributed to the enhanced wettability of the separator towards electrolyte stemmed from the nanofibrous structure,and the uniform lithium ion flux stabilized by the open metal sites of uniformly distributed HKUST-1 particles in the membrane during cycling. |
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