Tailoring the Nanoporosity and Photoactivity of Metal–Organic Frameworks With Rigid Dye Modulators for Toluene Purification

Abstract

Facile synthesis of hierarchically porous metal–organic frameworks (MOFs) with adjustable porosity and high crystallinity attracts great attention yet remains challenging. Herein, a micromolar amount of dye‐based modulator (Rhodamine B (RhB)) is employed to easily and controllably tailor the pore size of a Ti‐based metal–organic framework (MIL‐125‐NH2). The RhB used in this method is easily removed by washing or photodegradation, avoiding secondary posttreatment. It is demonstrated that the carboxyl functional group and the steric effects of RhB are indispensable for enlarging the pore size of the MIL‐125‐NH2. The resulting hierarchically porous MIL‐125‐NH2 (RH‐MIL‐125‐NH2) exhibits optimized adsorption and photocatalytic activity because the newly formed mesopore with defects concurrently facilitates mass transport of guest molecules (toluene) and photogenerated charge separation. This work offers a meaningful basis for the construction of hierarchically porous MOFs and demonstrates the superiority of the hierarchical pore structure for adsorption and heterogeneous catalysis.

Coordination modulation: a way to improve the properties of metal–organic frameworks

“…Furthermore, the study highlights that similar structural effects can also be achieved using the dye Eosin Y. 80…”

“…Furthermore, the study highlights that similar structural effects can also be achieved using the dye Eosin Y. 80 In addition to using large organic molecules, whole organic scaffolds can also act as modulators. In their work, Li et al show that porous styrene scaffolds can be used as structure-directing modulators in the synthesis of ZIF-8.…”

“…In the case of caffeine, the effect of these modulators is shown by interactions with the organic linkers via hydrogen bonds. 79,80 Among the largest representatives of this class are the porous polystyrenes. In this context, MOF formation is induced within the porous structure of the polystyrene framework itself.…”

Construction of hierarchical porous and polydopamine/salicylaldoxime functionalized zeolitic imidazolate framework-8 via controlled etching for uranium adsorption

“…2e, The PDA/SA-ZIF-8 was etched by EDTA, and the H-PDA/SA-ZIF-8 appeared as a mixture of type I and type IV isotherms with obvious hysteresis loops. 46 The pore size distributions of PDA/SA-ZIF-8 and H-PDA/SA-ZIF-8 were calculated using the nonlocal density functional theory (NLDFT) method (Fig. 2f), which showed that the peak of pristine PDA/SA-ZIF-8 appeared only in the range of micropores.…”