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Injecting fluids into deep underground geologic structures is a critical component to development of long-term strategies for managing greenhouse gas emissions and facilitating energy extraction operations. Recently, we reported that metal–organic frameworks are low-frequency, absorptive-acoustic metamaterial that may be injected into the subsurface to enhance geophysical monitoring tools used to track fluids and map complex structures. A key requirement for this nanotechnology deployment is transportability through porous geologic media without being retained by mineral-fluid interfaces. We used flow-through column studies to estimate transport and retention properties of five different polymer-coated MIL-101(Cr) nanoparticles (NP) in siliceous porous media. When negatively charged polystyrene sulfonate coated nanoparticles (NP-PSS-70K) were transported in 1 M NaCl, only about 8.4% of nanoparticles were retained in the column. Nanoparticles coated with polyethylenimine (NP-PD1) exhibited significant retention (> 50%), emphasizing the importance of complex nanoparticle-fluid-rock interactions for successful use of nanofluid technologies in the subsurface. Nanoparticle transport experiments revealed that nanoparticle surface characteristics play a critical role in nanoparticle colloidal stability and as well the transport. [ABSTRACT FROM AUTHOR]

Adsorption‐based cooling is an energy‐efficient renewable‐energy technology that can be driven using low‐grade industrial waste heat and/or solar heat. Here, we report the first exploration of fluorocarbon adsorption using porous covalent organic polymers (COPs) for this cooling application. High fluorocarbon R134a equilibrium capacities and unique overall linear‐shaped isotherms are revealed for the materials, namely COP‐2 and COP‐3. The key role of mesoporous defects on this unusual adsorption behavior was demonstrated by molecular simulations based on atomistic defect‐containing models built for both porous COPs. Analysis of simulated R134a adsorption isotherms for various defect‐containing atomistic models of the COPs shows a direct correlation between higher fluorocarbon adsorption capacities and increasing pore volumes induced by defects. Combined with their high porosities, excellent reversibility, fast kinetics, and large operating window, these defect‐containing porous COPs are promising for adsorption‐based cooling applications. [ABSTRACT FROM AUTHOR]

Adsorption cooling, structure defects, fluorocarbon refrigerants, porous covalent organic polymers Keywords: adsorption cooling; structure defects; fluorocarbon refrigerants; porous covalent organic polymers EN adsorption cooling structure defects fluorocarbon refrigerants porous covalent organic polymers 17894 17894 1 08/05/21 20210809 NES 210809 B Defekthaltige kovalente organische Polymere b sind vielversprechend für adsorptionsbasierte Kühlanwendungen. Innentitelbild: Porous Covalent Organic Polymers for Efficient Fluorocarbon-Based Adsorption Cooling (Angew. [Extracted from the article]

In their Research Article on page 18037, Guillaume Maurin, Radha Kishan Motkuri, and co-workers present experimental and computational evidence that mesoporous defects in the framework play a key role for the unique overall linear-shaped R134a adsorption isotherm and the exceptional adsorption uptake. Inside Cover: Porous Covalent Organic Polymers for Efficient Fluorocarbon-Based Adsorption Cooling (Angew. Keywords: adsorption cooling; structure defects; fluorocarbon refrigerants; porous covalent organic polymers EN adsorption cooling structure defects fluorocarbon refrigerants porous covalent organic polymers 17750 17750 1 08/05/21 20210809 NES 210809 B Defective covalent organic polymers b are promising for adsorption-based cooling applications. [Extracted from the article]