The MOF⁺ Technique: A Potential Multifunctional Platform

Abstract

Pores are the most ubiquitous moieties in metal-organic frameworks (MOFs). Based on pore, the MOFs can thus communicate with various guest molecules, leading to many important applications such as storage, separation, and catalysis. However, its abundant surface, presenting another basic component, is often ignored. This is primarily due to the intrinsic stability of surface atoms of MOFs towards external surroundings, or an opposite status of badly destroying the structure of MOFs. In this concept article, we present a novel MOF technique, which is a complete surface technique. The design, mechanism, applications, challenges and perspectives are discussed in detail.

Hybrid Catalyst of a Metal–Organic Framework, Metal Nanoparticles, and Oxide That Enables Strong Steric Constraint and Metal–Support Interaction for the Highly Effective and Selective Hydrogenation of Cinnamaldehyde

“…We know that the aperture of Co-MOF-74 is about 1.1 nm, which suggests that the loading of Pt NPs must occur on the surface of the Co-MOF-74 samples rather than within the pore because of the big size of the as-synthesized Pt NPs (2.4 ± 0.3 nm). As disclosed in our recent reports, the formation of Fe 2 O 3 due to the surface reaction of Fe 3+ and Co-MOF-74 also occurred on the surface of the Co-MOF-74 samples, while as observed in the literature, coprecipitation facilitates generation of the Pt-encapsulated hybrid composite . In this regard, in this system the formation of Pt@Fe 2 O 3 on the surface of the Co-MOF-74 samples is expected; thus, the resulting material can be viewed as Co-MOF-74@(Pt@Fe 2 O 3 ).…”

“…The difference is the iron oxide. In our MOF + technique, its formation is in an in situ manner because of the surface reaction of Fe 3+ and Co-MOF-74, whereas in the established coprecipitation method, its formation is tuned by the temperature and pH values . The resulting composite was further characterized by powder X-ray diffraction (PXRD; Figure S5), TEM (Figure ), high-resolution TEM (Figure S6), X-ray photoelectron spectroscopy (XPS; Figure S7), and N 2 adsorption at 77 K (Figure S8), suggesting the composition of Fe 2 O 3 , Pt NPs, and Co-MOF-74.…”

“…To combine both Fe 2 O 3 and the MOF support together and enhance the metal–support interactions, the loading of Pt NPs onto mixed supports was implemented by our recently developed MOF + technique . Note that the MOF + technique can significantly prevent reaggregation during the loading of Pt NPs onto the support, leading to well-dispersed loading with a size of 2.6 ± 0.3 nm (Figure ).…”

Ultralow-Content Palladium Dispersed in Covalent Organic Framework for Highly Efficient and Selective Semihydrogenation of Alkynes

“…As is well-known, support materials play a crucial role in the catalytic performance because a suitable support often leads to strong interaction between the active metal and support, which is good for enhancing the catalytic activity. − Thus, a variety of different supports including porous silica, carbon materials, graphene, metal oxide, polymers, and metal–organic frameworks (MOFs) have been used to load noble-metal Pd for the selective hydrogenation of alkynes. For example, Ulan et al reported a CaCO 3 -supported Pd catalyst (Pd/CaCO 3 treated by Pb salts) for the selective hydrogenation of 2-hexyne .…”

A Sonochemically-Synthesized Microporous Metal-Organic Framework for the Rapid and Efficient Ultrasonic-Assisted Removal of Mercury (II) Ions in a Water Solution and a Study of the Antibacterial Activity

“…Conventional adsorbents have deficiencies, such as high operating and maintenance costs, the emission of secondary pollutants and, most importantly, a poor performance at very low concentrations. The preparation of metal-organic frameworks (MOFs) is an effective method for the absorption and selective separation of metal ions from water [12][13][14][15]. An MOF is a solid absorbent material made of secondary building units (SBUs), which includes metal clusters and organic linkers that create three-dimensional grids [16,17].…”