Nowadays, Covalent-Organic Frameworks (COFs) are deemed to be the utmost trending and leading materials worldwide, counting on their highly porous nature and phenomenal thermodynamic stability. Owing to a highly ordered organic network having diverse strong covalent linkages, these materials have elucidated their suitability in photoelectricity, drug delivery, semiconductors, gas storage and separation, emission, proton conduction, catalysis, etc. To add on the functionality, these materials are been coupled with other functional materials to amalgamate COFs composites. Such COFs composites offer countless opportunities for valuable applications. Herein, in this review we report and underpin the existing synthesis methods for COFs and their composites along with their analytical applications in various fields with special reference to separation and sensing. A conclusive discussion on their future perspectives and challenges is made to benefit the readers.

Stepwise hierarchical and rational synthesis of porous zinc phosphate frameworks by predictable and directed assembly of easily isolable tetrameric zinc phosphate [Zn(dipp)(solv)]4 (dippH2 = diisopropylphenyldihydrogen phosphate; solv = CH3OH or dimethyl sulfoxide) with D4R (double-4-ring) topology has been achieved. The preformed and highly robust D4R secondary building unit can be coordinatively interconnected through a varied choice of bipyridine-based ditopic spacers L1-L7 to isolate eight functional zinc phosphate frameworks, [Zn4(dipp)4(L1)1.5(DMSO)]·4H2O (2), [Zn4(dipp)4(L2)1.5(CH3OH)] (3), [Zn4(dipp)4(L1)2] (4), [Zn4(dipp)4(L3)2] (5), [Zn4(dipp)4(L4)2] (6), [Zn4(dipp)4(L5)2] (7), [Zn4(dipp)4(L6)2] (8), and [Zn4(dipp)4(L7)2] (9), in good yield. The preparative procedures are simple and do not require high pressure or temperature. Surface area measurements of these framework solids show that the guest accessibility of the frameworks can be tuned by suitable modification of bipyridine spacers.

Copper amine oxidase (CAO), consisting of the topoquinone (TPQ) cofactor, catalyzes the oxidation of primary amines to aldehyde. We have successfully addressed this issue through isolation of a copper complex which mimics the active-site structure as well as the function of CAO. This inimitable complex, consisting of two TPQ-like side-arms, formed by ambient aerial oxidation of a precursor Schiff base complex, is the most efficient homogeneous catalyst for quantitative oxidation of primary benzylic amines to corresponding secondary imines under ambient conditions within 30 min. The longstanding contention of actual involvement of Cu­(II) in the catalysis is resolved through quenching experiments of Cu­(II) superoxo species and detailed density functional theory studies.

The high tendency of water to get polluted is due to the extensive usability among all the resources. Amongst all the anthropogenic pollutants, a variety of synthetic non-biodegradable dyestuff are...

Insertion of molecular metal oxides, i.e. polyoxometalates (POMs), into metal-organic frameworks (MOFs), opens up new research opportunities in various fields, particularly in catalysis. POM/MOF composites have strong acidity, oxygen-rich surface,...