Porous materials towards CO2 capture and direct calorimetric measurement of adsorption heat

Metal-Organic frameworks (MOFs) and porous molecular materials represent a new platform for achieving and exploring high-performance sorptive properties and gas transport. The key lies in the modular nature of these materials, which allows for tuning and functionalization towards improved gas capture. Self-assembly of polyfunctional molecules containing multiple charges, namely, tetrahedral tetra-sulfonate anions and bifunctional linear cations, resulted in a permanently porous crystalline material in which the channels are decorated by double helices of electrostatic charges that governed the association and transport of CO2 molecules.[1] An isoreticular series of Fe-MOFs with varying decoration of fluorine atoms within their channel walls as a method for modulating the CO2 adsorption properties.[2] In these systems we studied the guest recognition within the porous materials in relation to the structural moieties and modulation. A host of complementary experimental and computational techniques gives a holistic view of the host-CO2 properties towards the potential selective removal of CO2 from other gases. GCMC and DFT were employed for a detailed description of the CO2 diffusion and interactions in the porous materials. CO2–matrix adsorption enthalpies was accurately measured in-situ by simultaneous acquisition of microcalorimetric and volumetric-isotherm data. Accurate adsorption heats are very importation for sorption-based applications and devices, thus highlighting the importance of direct measurement of the adsorption heat. This also serves a way to benchmark the mathematical models and protocols for adsorption heats derived from sorption isotherms. References 1. Xing, G.; Bassanetti, I.; Bracco, S.; Negroni, M.; Bezuidenhout, C.; Ben, T.; Sozzani, P.; Comotti, A., Chemical Science 2019, 10 (3), 730-736. 2. Perego, J.; Bezuidenhout, C. X.; Pedrini, A.; Bracco, S.; Negroni, M.; Comotti, A.; Sozzani, P., Journal of Materials Chemistry A 2020, 8 (22), 11406-11413.