Impact of water and metal oxide nanoparticles on the structure and properties of 1-ethyl-3-methylimidazolium methylsulfate ionic liquid for solar thermal applications

For the first time, the impact of water and metal-oxide nanoparticles (MONPs) on the electronic structure and optical properties of 1-ethyl-3-methylimidazolium methylsulfate (C2mim MS) ionic liquid (IL) is reported. Offswitching of cation-anion interaction and emergence of new peak at 2970 cm-1 was observed indicating change in the interaction strength and conformation of ethyl chain upon dilution. Optical absorption properties and viscosity of neat IL significantly enhanced by dispersing a very low volume fraction of MONPs. DFT calculations provide a clue of the formation of a protective layer of IL around NPs owing to simultaneous cationicanionic interaction with the MONPs.

Automated summary

The impact of water and metal-oxide nanoparticles (MONPs) on the electronic structure and optical properties of 1-ethyl-3-methylimidazolium methylsulfate (C2mim MS) ionic liquid (IL) is reported for the first time. Offswitching of cation-anion interaction and emergence of a new peak at 2970 cm-1 indicate changes in the interaction strength and conformation of the ethyl chain upon dilution. The dispersion of a very low volume fraction of MONPs significantly enhances the optical absorption properties and viscosity of the neat IL. DFT calculations suggest the formation of a protective layer of IL around NPs due to simultaneous cationic and anionic interaction with the MONPs.