Affordable and Clean Energy (SDG 7), Responsible Consumption and Production (SDG 12) Neil Robinson Department of Chemical Engineering, The University of Western Australia
Characterising interfacial phenomena in porous materials with low-field magnetic resonance While solid – fluid interactions underpin the efficacy of functional porous materials across a diverse array of chemical reaction and separation processes of direct relevance to SDG7, detailed characterisation of interfacial phenomena within such systems is often hampered by their optically opaque nature. Motivated by the need to bridge this capability gap, this poster will highlight the application of low-field two-dimensional 1 H nuclear spin relaxation measurements as a non-invasive probe of adsorbate identity and interfacial dynamics [1], taking the relaxation characteristics exhibited by liquid hydrocarbon adsorbates confined to a model mesoporous silica as examples. Based on recent observations [2], we will demonstrate the clear capacity of observed T 1 – T 2 relaxation time distributions in distinguishing functional group-specific relaxation phenomena across a diverse range of alcohols and carboxylic acids employed as solvents, reagents, and liquid hydrogen carriers, wherein distinct relaxation responses may be assigned to the alkyl and hydroxyl moieties of each confined liquid (see Figure 1). Recent advances in utilising these observations to track competitive liquid/liquid displacement processes within such materials will also be discussed; such techniques are anticipated to provide critical information regarding solvent selection in liquid-phase catalytic systems of relevance to green chemical processes. Neil Robinson* Department of Chemical Engineering, The University of Western Australia While solid–fluid interactions underpin the efficacy of functional porous materials across a diverse array of chemical reaction and separation processes of direct relevance to SDG7, detailed characterisation of interfacial phenomena within such systems is often hampered by their optically opaque nature. Motivated by the need to bridge this capability gap, this poster will highlight the application of low- field two-dimensional 1 H nuclear spin relaxation measurements as a non-invasive probe of adsorbate identity and interfacial dynamics [1], taking the relaxation characteristics exhibited by liquid hydrocarbon adsorbates confined to a model mesoporous silica as examples. Based on recent observations [2], we will demonstrate the clear capacity of observed T1 – T2 relaxation time distributions in distinguishing functional group-specific relaxation phenomena across a diverse range of alcohols and carboxylic acids employed as solvents, reagents, and liquid hydrogen carriers, wherein distinct relaxation responses may be assigned to the alkyl and hydroxyl moieties of each confined liquid (see Figure 1). Recent advances in utilising these observations to track competitive liquid/liquid displacement processes within such materials will also be discussed; such techniques are anticipated to provide critical information regarding solvent selection in liquid-phase catalytic systems of relevance to green chemical processes.
Ethanol
2-Propanol
Propanoic acid
Figure 1. 1 H T1 – T2 relaxation time distributions obtained from polar hydrocarbon liquids confined within mesoporous silica. Correlation peaks observed at small and large T1/T2 ratios are attribution to alkyl and hydroxyl 1 H group relaxation, respectively. References 1. N Robinson et al., “Direct correlation between adsorption energetics and nuclear spin relaxation in a liquid-saturated catalyst material”, ChemPhysChem, 2018, 19, 2472-2479 2. N Robinson et al., “Low-field functional group resolved nuclear spin relaxation in mesoporous silica”, ACS Appl. Mater. Interfaces, 2021, 13, 54476-54485 1 – T 2 relaxation time distributions obtained from polar hydrocarbon liquids confined within mesoporous silica. Correlation peaks observed at small and large T 1 / T 2 ratios are attribution to alkyl and hydroxyl 1 H group relaxation, respectively. References [1] N Robinson et al ., “Direct correlation between adsorption energetics and nuclear spin relaxation in a liquid - saturated catalyst material”, ChemPhysChem , 2018, 19 , 2472-2479 [2] N Robinson et al ., “Low - field functional group resolved nuclear spin relaxation in mesoporous silica”, ACS Appl. Mater. Interfaces , 2021, 13 , 54476-54485 Figure 1. 1 H T
P18
© The Author(s), 2023
Made with FlippingBook Learn more on our blog