Recent Progress in Metal–Organic Framework-Derived Nanostructures in the Removal of Volatile Organic Compounds

Abstract

Air is the most crucial and life-supporting input from nature to the living beings of the planet. The composition and quality of air significantly affects human health, either directly or indirectly. The presence of some industrially released gases, small particles of anthropogenic origin, and the deviation from the normal composition of air from the natural condition causes air pollution. Volatile organic compounds (VOCs) are common contaminants found as indoor as well as outdoor pollutants. Such pollutants represent acute or chronic health hazards to the human physiological system. In the environment, such polluted gases may cause chemical or photochemical smog, leading to detrimental effects such as acid rain, global warming, and environmental pollution through different routes. Ultimately, this will propagate into the food web and affect the ecosystem. In this context, the efficient removal of volatile organic compounds (VOCs) from the environment remains a major threat globally, yet satisfactory strategies and auxiliary materials are far from being in place. Metal–organic frameworks (MOFs) are known as an advanced class of porous coordination polymers, a smart material constructed from the covalently bonded and highly ordered arrangements of metal nodes and polyfunctional organic linkers with an organic–inorganic hybrid nature, high porosities and surface areas, abundant metal/organic species, large pore volumes, and elegant tunability of structures and compositions, making them ideal candidates for the removal of unwanted VOCs from air. This review summarizes the fundamentals of MOFs and VOCs with recent research progress on MOF-derived nanostructures/porous materials and their composites for the efficient removal of VOCs in the air, the remaining challenges, and some prospective for future efforts.

The Complexity of Comparative Adsorption of C6 Hydrocarbons (Benzene, Cyclohexane, n-Hexane) at Metal–Organic Frameworks

“…MOFs are typically three-dimensional coordination networks with potential voids from the combination of metal clusters (secondary building units, SBUs) and organic ligands (called linkers) [ 14 ]. MOFs have already been investigated for the adsorption of VOCs such as n -hexane, xylene, toluene, acetaldehyde in vapor [ 7 , 15 ], liquid phase [ 16 , 17 ], or under humid conditions [ 18 ]. MOFs offer advantages [ 19 ] for VOC removal over materials [ 20 ] like zeolites [ 21 ], activated carbon [ 22 ], or silica gel [ 23 ].…”

Efficient extraction based on a polydimethylsiloxane/bimetallic ZnCo-MOF carbonization sponge coupled with GC-MS for the rapid analysis of volatile compounds in cumin

“…[30][31][32][33][34] Among these, MOFs have demonstrated great application potential in sample pretreatment because of their inherent advantages, such as structural diversity, large surface areas, more ordered pore structure, and facile synthesis. [35][36][37][38] In recent years, the direct carbonization of MOFs under inert conditions to prepare nanoporous carbon materials has gained increasing interest. Compared with other carbon materials, nanoporous carbon has excellent characteristics such as outstanding surface area, ultrahigh porosity, and ease of functionalization.…”

In Operando Spectroscopic Ellipsometry Investigation of MOF Thin Films for the Selective Capture of Acetic Acid

“…In the continuous quest of valuable solutions for air quality, metal–organic frameworks (MOFs) are recognized as an emerging class of adsorbents toward the abatement of VOCs including CCs owing to their large surface area and chemical functionality. − Specific adsorption sites can be introduced in the MOF backbone either on their inorganic nodes (Lewis acid groups) or through the introduction of functional groups (−CF 3 , −alkyl chain, or – NH 2 ) on the organic linker. Their chemical diversity, tunable hydrophobicity/hydrophilicity balance, and selective sorption properties are thus exploited to optimize the host/guest interactions involved in numerous applications including gas storage, gas/liquid separation, sensing, energy conversion/storage, and catalysis. ,, MOFs have also been considered for the capture and catalytic degradation of toxic industrial chemicals, chemical warfare agents, and also environmental VOCs, even at trace levels in ambient conditions. − However, until now, only a few studies have been reported on MOFs for CCs capture under humid conditions. − Notably, most of the previously reported works have studied the efficiency of MOFs for the removal of only a single CC (most prominently formaldehyde) while CCs are present in the indoor environment as a gaseous mixture in which water is the most abundant interfering species.…”