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Metal–organic frameworks (MOFs) have attracted a special attention due to outstanding porosity, adjustable pore sizes, and huge opportunities in varying organic–inorganic ...compositions. Enormous studies conducted so far on MOFs indicate their high potential in catalysis, gas adsorption, drug delivery, water treatment, energy storage, among others. However, mass production of MOFs is still limited mainly due to the non-economic, non-green and complex synthesis methods. Mechanochemistry is an alternative solution for efficient and environmentally friendly syntheses of various MOFs. Fast and solvent-free or solvent-less mechanosynthesis seems to be a very powerful versatile method for obtaining these advanced porous materials. The mechanochemical concept was used for the preparation of various MOFs including the most popular structures: MOF-5, ZIF-8, HKUST-1, MIL-101, UiO-66. These MOFs feature high specific surface areas, comparable to those prepared by conventional solvent-based methods. Furthermore, mechanochemistry was successfully used for the synthesis of non-conventional multimetallic MOFs and previously unreported solid phases. This review shows the recent developments, challenges and perspectives of green synthesis of diverse MOF structures using mechanochemistry. Besides describing the mechanochemical synthesis of MOFs, some achievements in green applications are also summarized. Importantly, current trends in research suggests for further development of these fields i.e., harmful gas adsorption, water treatment, and energy storage.
Clean energy sources and global warming are among the major challenges of the 21st century. One of the possible actions toward finding alternative energy sources and reducing global warming are ...storage of H2 and CH4, and capture of CO2 by using highly efficient and low-cost adsorbents. Graphene and graphene-based materials attracted a great attention around the world because of their potential for a variety applications ranging from electronics, gas sensing, energy storage and CO2 capture. Large specific surface area of these materials up to ~3000m2/g and versatile modification make them excellent adsorbents for diverse applications. Here, graphene-based adsorbents are reviewed with special emphasis on their adsorption affinity toward CO2, H2 and CH4. This review shows that graphene derivatives obtained mainly via “chemical exfoliation” of graphite and further modification with polymers and/or metal species can be very effective sorbents for CO2 and other gases and can compete with the currently used carbonaceous or non-carbonaceous adsorbents. The high adsorption capacities of graphene-based materials are mainly determined by their unique nanostructures, high specific surface areas and tailorable surface properties, which make them suitable for storage or capture of various molecules relevant for environmental and energy-related applications.
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•Tuning adsorption properties of graphene by coupling with nanoparticles•Appraisal of properties of graphene materials for CO2, H2 and CH4 adsorption•Comparison of gas adsorption affinity for graphene, activated carbons and MOFs
In this feature article we focus on the main developments in the area of ordered mesoporous materials (OMMs) since their discovery in 1992, which is considered one of the milestones in the history of ...porous materials. Nowadays, there are almost unlimited opportunities in the synthesis of composite- or modified OMMs by using soft- and hard-templating strategies and related methods. Nevertheless, there is still a great challenge to obtain diverse OMMs with well-developed porosity and desired morphology, crystallinity and surface properties. The evolution of the leading OMM members: silicas, organosilicas, metal oxides, carbons, metal-organic frameworks and zeolites, including the main factors affecting their development, is briefly summarized with special emphasis on the authors' accomplishments in this area. Additionally, recent advancements, challenges and prospects in the field of OMMs are presented.
This feature article presents the main developments in the area of ordered mesoporous materials (OMMs) since their discovery in 1992, which is considered one of the milestones in the history of porous materials.
Conventional synthesis methods of functional materials are usually time- and energy consuming and contribute to the accumulation of waste solvents. An alternative solution is the use of ...environmentally friendly recipes such as mechanochemical synthesis, which may be employed for large-scale production of materials. Mechanochemistry has been applied in various areas, such as metallurgy, mineral processing, construction and synthesis of organic compounds, and currently it is experiencing a renaissance because of its successful implementation for the synthesis of diverse organic, inorganic and organic-inorganic hybrid nanomaterials. Here mechanochemical synthesis of highly porous materials is reviewed with special emphasis on novel sorbents. Mechanochemically-assisted methods are well suited for the preparation of highly porous carbons (such as lignin- or tannin-derived carbons), metal-organic frameworks (
e.g.
, MOF-5, MIL-101 and U-67) or covalent organic frameworks with specific surface areas up to 3500 m
2
g
−1
. Recently, ball milling was also utilized for the synthesis of ordered coordination polymers and perfectly ordered mesoporous carbons. Nowadays, mechanochemistry has become a powerful and quite universal method for the preparation of various materials. Hence, there is a need for a review summarizing the current accomplishments in this field. Most of the mechanochemically obtained porous materials reported so far have been designed for adsorption, catalysis and energy storage related applications.
Mechanochemistry became a powerful and popular method for the preparation of various porous materials.
Ultrasounds are commonly used in medical imaging, solution homogenization, navigation, and ranging, but they are also a great energy source for chemical reactions. Sonochemistry uses ultrasounds and ...thus realizes one of the basic concepts of green chemistry, i.e., energy savings. Moreover, reduced reaction time, mostly using water as a solvent, and better product yields are among the many factors that make ultrasound-induced reactions greener than those performed under conventional conditions. Sonochemistry has been successfully implemented for the preparation of various materials; this review covers sonochemically synthesized nanoporous materials. For instance, sonochemical-assisted methods afforded ordered mesoporous silicas, spherical mesoporous silicas, periodic mesoporous organosilicas, various metal oxides, biomass-derived activated carbons, carbon nanotubes, diverse metal-organic frameworks, and covalent organic frameworks. Among these materials, highly porous samples have also been prepared, such as garlic peel-derived activated carbon with an apparent specific surface area of 3887 m
/g and MOF-177 with an SSA of 4898 m
/g. Additionally, many of them have been examined for practical usage in gas adsorption, water treatment, catalysis, and energy storage-related applications, yielding satisfactory results.
Metal–organic structures have great potential for practical applications in many areas. However, their widespread use is often hindered by time-consuming and expensive synthesis procedures that often ...involve hazardous solvents and, therefore, generate wastes that need to be remediated and/or recycled. The development of cleaner, safer, and more sustainable synthesis methods is extremely important and is needed in the context of green chemistry. In this work, a facile mechanochemical method involving water-assisted ball milling was used for the synthesis of MOF-303. The obtained MOF-303 exhibited a high specific surface area of 1180 m2/g and showed an excellent CO2 adsorption capacity of 9.5 mmol/g at 0 °C and under 1 bar.
Highly porous activated carbons were synthesized via the mechanochemical salt-templating method using both sustainable precursors and sustainable chemical activators. Tannic acid is a polyphenolic ...compound derived from biomass, which, together with urea, can serve as a low-cost, environmentally friendly precursor for the preparation of efficient N-doped carbons. The use of various organic and inorganic salts as activating agents afforded carbons with diverse structural and physicochemical characteristics, e.g., their specific surface areas ranged from 1190 m
·g
to 3060 m
·g
. Coupling the salt-templating method and chemical activation with potassium oxalate appeared to be an efficient strategy for the synthesis of a highly porous carbon with a specific surface area of 3060 m
·g
, a large total pore volume of 3.07 cm
·g
and high H
and CO
adsorption capacities of 13.2 mmol·g
at -196 °C and 4.7 mmol·g
at 0 °C, respectively. The most microporous carbon from the series exhibited a CO
uptake capacity as high as 6.4 mmol·g
at 1 bar and 0 °C. Moreover, these samples showed exceptionally high thermal stability. Such activated carbons obtained from readily available sustainable precursors and activators are attractive for several applications in adsorption and catalysis.
In this work, we test metal–organic frameworks (MOFs) as sorbents in the solid-phase extraction (SPE) technique to determine chemical warfare agents (CWAs) and their related compounds in water ...samples. During this study, we used 13 target compounds to test the selectivity of MOFs thoroughly. Three MOFs were used: MIL-100(Fe), ZIF-8(Zn), and UiO-66(Zr). The obtained materials were characterized using FT-IR/ATR, SEM, and XRD. CWA’s and related compounds were analyzed using gas chromatography coupled with tandem mass spectrometry (GC-MS/MS). The effect of the type of elution solvent and the amount of sorbent (MOFs) in the column on the efficiency of the conducted extraction were verified. The LOD ranged from 0.04 to 7.54 ng mL−1, and the linearity range for the analytes tested extended from 0.11/22.62 (depending on the compound) to 1000 ng mL−1. It was found that MOFs showed the most excellent selectivity to compounds having aromatic rings in their structure or a “spread” spatial structure. The best recoveries were obtained for DPAA, CAP, and malathion. Environmental water samples collected from the Baltic Sea were analyzed using an optimized procedure to verify the developed method’s usefulness.
Mesoporous phenolic resin-based carbons were prepared by soft-templating synthesis and activated by KOH. It is shown that the KOH activation of these mesoporous carbons results in a substantial ...increase of microporosity with simultaneous preservation of mesoporous structure. The resulting micro- and mesoporous carbons possess high surface area and large volume of mesopores.
A facile mechanochemical method was used for the synthesis of ordered mesoporous carbons (OMCs) with well-dispersed metal nanoparticles. The one-pot ball milling of tannins with a metal salt in the ...presence of a block copolymer followed by thermal treatment led to Ni- or Pt-embedded OMCs with high specific surface areas (up to 600 m2·g−1) and large pore volumes (up to ~0.5 cm3·g−1). The as-prepared OMC-based samples exhibited hexagonally ordered cylindrical mesopores with narrow pore size distributions (average pore size ~7 nm), which implies sufficient long-range copolymer-assisted self-assembly of the tannin-derived polymer upon milling even in the presence of a metal salt. The homogenous decoration of carbons with small-sized metal (Ni or Pt) particles was essential to provide H2 storage capacities up to 0.33 wt.% at 25 °C and under 100 bar. The presented synthesis strategy seems to have great potential in the practical uses of functionalized polymers and carbons for applications in adsorption and catalysis.
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