However, their work only focused on the crystal structure, and did not explore the pore and function of the material. In the 1990s, Wuest and his colleagues discovered a large number of HOFs, pioneering the development of diaminotriazine (DAT) groups as hydrogen bond interaction sites to construct stable hydrogen bond networks. In the decades that followed, however, HOFs research stalled. reported a two-dimensional network crystal structure formed by hydrogen bonding forces of 1,3,5-benzoic acid as an organic unit. Figure 1a presents some crucial time points for the HOFs’ development. Actually, the history of hydrogen-bonded organic frameworks goes back even further. HOFs are pure organic framework materials that use hydrogen bonding as one of the main forces to connect the organic structure primitives with electron-acceptor bodies, and at the same time, they are formed through self-assembly in other weak interactions, such as π-π interaction, van der Waals interaction, and dipole-dipole interaction. Overall, the catalysts required in the synthesis process are expensive, the reaction conditions are strict, and it is difficult to obtain large-scale crystalline products, which hinders their application and development in many fields.Ĭompared with traditional crystalline porous materials, HOFs have attracted extensive attention due to their unique characteristics. Compared with MOFs, COFs have no metal nodes, but the synthesis conditions are relatively harsh. In the framework of MOFs, metal nodes have certain toxicity, which limits their application in biological and drug delivery fields. The stability of MOFs (especially in water) has always been a difficult problem to solve. However, there are some drawbacks to MOFs and COFs. MOFs and COFs have been extensively studied due to their high specific surface area, flexible structure, abundant porosity, and good thermal stability. Porous materials, such as porous organic polymers (POPs), covalent organic frameworks (COFs), metal-organic frameworks (MOFs) and hydrogen-bonded organic frameworks (HOFs), have attracted more and more attention because of their broad application prospects in the environmental remediation fields. It is hoped that this work will help develop widespread applications for HOFs in removing a variety of pollutants from the environment. Finally, the current challenges and further studies of HOFs (such as functional modification, molecular simulation, application extension as remediation of contaminated soil, and cost assessment) are discussed. In addition, the applications of HOF-based materials in the field of environmental remediation are introduced, including adsorption and separation (NH 3, CO 2/CH 4 and CO 2/N 2, C 2H 2/C 2H e and C eH 6, C 2H 2/CO 2, Xe/Kr, etc.), heavy metal and radioactive metal adsorption, organic dye and pesticide adsorption, energy conversion (producing H 2 and CO 2 reduced to CO), organic dye degradation and pollutant sensing (metal ion, aniline, antibiotic, explosive steam, etc.). This work summarizes some rules for constructing stable HOFs and the synthesis of HOF-based materials (synthesis of HOFs, metallized HOFs, and HOF-derived materials). HOFs are widely used in environmental remediation due to their high specific surface area, ordered pore structure, pore modifiability, and post-synthesis adjustability of various physical and chemical forms. If one layer of latex was used in the past and removal is not feasible, Ion-Bond will penetrate and can help waterproof the concrete.The hydrogen-bonded organic frameworks (HOFs) are a class of porous materials with crystalline frame structures, which are self-assembled from organic structures by hydrogen bonding in non-covalent bonds π-π packing and van der Waals force interaction. Penetrates Latex Paint – Latex paint is porous.Humidity – Aids in reducing water vapor transmission through the substrate.Minimizes the infiltration of water vapor and gases, while still allowing the substrate to dry out. Paintable – Leaves the surface suitable for paints, adhesives, thin-set, and patching compounds.Leaves the natural appearance of the concrete. Slip Resistant – Does not coat the surface.Long-Lasting Seal – When used indoors and on walls, the waterproofing seal is practically permanent!.Waterborne, non-toxic, non-flammable, noncorrosive. Most homeowners are not aware that common “waterproofing” silane/siloxane or acrylic concrete sealers are not suitable for basements because they get pushed off by negative water pressure. Negative Side Water – Durable to seal against hydrostatic pressure.Penetrates into most hard-troweled concrete surfaces. Highly Penetrates – Penetrates up to 1.5″ into concrete three times deeper than typical siloxane sealers.Waterproofs – Indoor/Outdoor Concrete, Brick, Porous Masonry.
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