Search

The incorporation of two-dimensional (2D) functional nanosheets in polymeric membranes is a promising material strategy to overcome their inherent performance trade-off behavior. Herein, we report a novel nanocomposite membrane design by incorporating MXene, a 2D sheet-like nanoarchitecture known for its advantageous lamellar morphology and surface functionalities, into a cross-linked polyether block amide (Pebax)/poly(ethylene glycol) methyl ether acrylate (PEGMEA) blend matrix, which delivered exceptional CO 2 /N 2 and CO 2 /H 2 separation performances that are critical to industrial CO 2 capture applications. The finely dispersed Ti 3 C 2 T x nanosheets in the blend polymer matrix led to an expansion of the free volume within the resultant mixed matrix membrane (MMM), giving rise to a substantially enhanced CO 2 permeability of up to 1264.6 barrer, which is 102% higher than that of the pristine polymer. Moreover, these MXene-incorporated MMMs exhibited preferential sorption for CO 2 over light gases, which contributed to an exceptional CO 2 /N 2 and CO 2 /H 2 selectivity (64.3 and 19.2, respectively) even at a small loading of only 1 wt %, allowing the overall performance to not only surpass the latest upper bounds but also exceed many previously reported high-performance nanosheet-based nanocomposite membranes. Long-term performance tests have also demonstrated the good stability of these membranes. This composite membrane design strategy reveals the remarkable potential of combining a blend copolymer matrix with ultrathin MXene nanosheets to achieve superior gas separation performance for environmentally important gas separations.

Lithium-ion batteries (LIBs) are widely regarded as a promising electrochemical energy storage device, due to their high energy density and good cycling stability. To date, the development of anode materials for LIBs is still confronted with many serious problems, and much effort is required for constructing more ideal anode materials. Herein, starting with metal-organic frameworks (MOFs), an amorphous VO x coated Fe 3 O 4 /C hierarchical nanospindle has been successfully synthesized. The obtained Fe 3 O 4 /C@VO x nanospindle has a uniform particle size of ∼100 nm in diameter and ∼400 nm in length and consists of ultrafine Fe 3 O 4 nanoparticles (∼5 nm) embedded in a porous carbon matrix as the core and an amorphous VO x layer as the shell. Notably, as the anode material for LIBs, Fe 3 O 4 /C@VO x delivers a high coulombic efficiency (74.2%) and a large capacity of 845 mA h g -1 after 500 cycles at 1000 mA g -1 . A prominent discharge reversible capacity of 340 mA h g -1 is also still retained at 5000 mA g -1 . More importantly, the presented facile MOF-derived route could be easily extended to other functional materials for widespread applications.