Great attention has been given to metal–organic frameworks (MOFs)-derived solid bases because of their attractive structure and catalytic performance in various organic reactions. The extraordinary skeleton structure of MOFs provides many possibilities for incorporation of diverse basic functionalities, which is unachievable for conventional solid bases. The past decade has witnessed remarkable advances in this vibrant research area; however, MOFs for heterogeneous basic catalysis have never been reviewed until now. Therefore, a review summarizing MOFs-derived base catalysts is highly expected. In this review, we present an overview of the recent progress in MOFs-derived solid bases covering preparation, characterization, and catalytic applications. In the preparation section, the solid bases are divided into two categories, namely, MOFs with intrinsic basicity and MOFs with modified basicity. The basicity can originate from either metal sites or organic ligands. Different approaches used for generation o...

Metal-Organic Frameworks for Heterogeneous Basic Catalysis.

Removal of hazardous organics from water using metal-organic frameworks (MOFs): plausible mechanisms for selective adsorptions.

Metal-organic frameworks (MOFs) have been recognized as one of the most important classes of porous materials due to their unique attributes and chemical versatility. Unfortunately, some MOFs suffer from the drawback of relatively poor stability, which would limit their practical applications. In the recent past, great efforts have been invested in developing strategies to improve the stability of MOFs. In general, stable MOFs possess potential toward a broader range of applications. In this review, we summarize recent advances in the design and synthesis of stable MOFs and MOF-based materials via de novo synthesis and/or post-synthetic structural processing. Also, the relationships between the stability and functional applications of MOFs are highlighted, and finally, the subsisting challenges and the directions that future research in this field may take have been indicated.

https://pubs.rsc.org/en/content/articlepdf/2019/SC/C9SC03916C

Improving MOF stability: approaches and applications

Metal–organic frameworks (MOFs) for the removal of emerging contaminants from aquatic environments

Mesoporous solid bases are extremely desirable in green catalytic processes, due to their advantages of accelerated mass transport, negligible corrosion, and easy separation. Great progress has been made in mesoporous solid bases in the last decade. In addition to their wide applications in the catalytic synthesis of organics and fine chemicals, mesoporous solid bases have also been used in the field of energy and environmental catalysis. Development of mesoporous solid bases is therefore of significant importance from both academic and practical points of view. In this review, we provide an overview of the recent advances in mesoporous solid bases, which is basically grouped by the support type and each category is illustrated with typical examples. Cooperative catalysts derived from the incorporation of additional functionalities (i.e. acid and metal) into mesoporous solid bases are also included. The fundamental principles of how to design and fabricate basic materials with mesostructure are highlighted. The mechanism of the formation of basic sites in different mesoporous systems is discussed as well.

Design and fabrication of mesoporous heterogeneous basic catalysts

This paper aims to improve the hydrothermal stability and catalytic activity of metal–organic frameworks (MOFs), which are believed to play an important role in the practical applications of MOFs in catalysis. Our strategy is to incorporate graphite oxide into a typical MOF, namely HKUST-1 (Cu3(BTC)2, BTC = 1,3,5-benzenetricarboxylic acid; HKUST = Hong Kong University of Science and Technology), and the properties of MOF are successfully tailored by use of this strategy. The obtained MOF/graphite oxide composites show enhanced porosity with high surface areas and some meso/macropores. For the composite containing 8.7 wt % of graphite oxide, the surface area reaches 1257 m2 g–1, which is obviously higher than pure HKUST-1 (841 m2 g–1). The pore structure of composites favors the access of reactant molecules to active sites and accelerates mass transfer in channels. Furthermore, the incorporation of graphite oxide creates a more hydrophobic environment surrounding metallic sites, which prevents the coordina...

https://pubs.acs.org/doi/pdf/10.1021/jp506335x

Improving Hydrothermal Stability and Catalytic Activity of Metal–Organic Frameworks by Graphite Oxide Incorporation

Metal–organic frameworks (MOFs) have attracted extensive attention due to their large surface area, diverse structures, and tuneable functionality. However, the poor hydrostability of most reported MOFs hinders their practical applications severely. In this paper, we report a strategy to modulate the properties of a typical MOF, namely MOF-5 [Zn4O(BDC)3; BDC = 1,4-benzenedicarboxylate] by hybridizing it with a natural clay (i.e. attapulgite), for the first time. A new kind of hybrid material resulting from the hybridization of the MOF and attapulgite was thus constructed. Our results showed that the hydrostability of the MOF was apparently improved due to the hybridization with attapulgite. The frameworks of MOF-5 were degraded seriously under the humid atmosphere, while the structure of the hybrid materials could be well preserved. We also demonstrated that the hybrid materials were highly active in the heterogeneous Friedel–Crafts alkylation reaction of benzyl bromide with toluene. The conversion of benzyl bromide reached ∼100% under the reaction conditions investigated. More importantly, the catalytic stability of the hybrid materials was significantly enhanced owing to the introduction of attapulgite. The activity could be well recovered with no detectable loss, and the conversion remained at ∼100% at the sixth run, which was apparently higher than that of MOF-5 (27.7% at the sixth run). The excellent hydrostability, catalytic activity, and reusability make the present materials highly promising for utilization as heterogeneous catalysts in practical applications.

Enhancing the hydrostability and catalytic performance of metal–organic frameworks by hybridizing with attapulgite, a natural clay

The invention discloses a high-stability metal organic skeleton hybrid material. The metal organic skeleton hybrid material has high hydrothermal stability, and comprises metal organic skeleton and attapulgite, wherein the mass ratio of the attapulgite to the metal organic skeleton is (0.005-0.7):1.

Lei Lu

Papers

Improving Hydrothermal Stability and Catalytic Activity of Metal–Organic Frameworks by Graphite Oxide Incorporation

Enhancing the hydrostability and catalytic performance of metal–organic frameworks by hybridizing with attapulgite, a natural clay

High-stability metal organic skeleton hybrid material, preparation method and application thereof