An insight into the strategies for the enhancement of the adsorptive performance of metal–organic frameworks (MOFs)
摘要
MOFs are good adsorbents for many food and environmental pollutants. This can be attributed to the fact that they are highly porous materials with tunable properties. Consequently, seeking ways to enhance the adsorption properties of MOFs has become a research hotspot in recent years. This paper explores various strategies employed by researchers to improve the adsorptive sequestration of pollutants from contaminated samples using MOF-based adsorbents. These strategies include formation of hierarchical pores, defect engineering, doping, and formation of composites. Defect engineering and formation of hierarchical pores expose more adsorption sites thereby facilitating rapid mass transfer and diffusion of pollutants through the MOF adsorbent. On the other hand, formation of composites and doping confer the adsorbent with additional functional moieties for the efficient adsorption of pollutants from the samples. In addition, they endow the MOF adsorbent with extra stability as well as enhancing hydrogen bonding, electrostatic and hydrophobic interactions. The paper also gives an outline of the challenges associated with the use of these modified MOFs as adsorbents as well as the future prospects.
Graphical abstract