As highlighted by the recent ChemComm web themed issue on ionic liquids, this field continues to develop beyond the concept of interesting new solvents for application in the greening of the chemical industry. Here some current research trends in the field will be discussed which show that ionic liquids research is still aimed squarely at solving major societal issues by taking advantage of new fundamental understanding of the nature of these salts in their low temperature liquid state. This article discusses current research trends in applications of ionic liquids to energy, materials, and medicines to provide some insight into the directions, motivations, challenges, and successes being achieved with ionic liquids today.

Developing effective catalysts based on earth abundant elements is critical for CO 2 electroreduction. However, simultaneously achieving a high Faradaic efficiency (FE) and high current density of CO (j CO) remains a challenge. Herein, we prepare a Mn single-atom catalyst (SAC) with a Mn-N 3 site embedded in graphitic carbon nitride. The prepared catalyst exhibits a 98.8% CO FE with a j CO of 14.0 mA cm −2 at a low overpotential of 0.44 V in aqueous electrolyte, outperforming all reported Mn SACs. Moreover, a higher j CO of 29.7 mA cm −2 is obtained in an ionic liquid electrolyte at 0.62 V overpotential. In situ X-ray absorption spectra and density functional theory calculations demonstrate that the remarkable performance of the catalyst is attributed to the Mn-N 3 site, which facilitates the formation of the key intermediate COOH * through a lowered free energy barrier.

The pyridinium-based ionic liquids (ILs) N-butylpyridinium tetrafluoroborate ([BPy][BF 4 ]), N-hexylpyridinium tetrafluoroborate ([HPy][BF 4 ]), and N-octylpyridinium tetrafluoroborate ([OPy][BF 4 ]) were found to be effective for the selective removal of aromatic heterocyclic sulfur compounds from diesel at room temperature. The results suggested that the structure and size of the cation greatly affect the extractive performance of ILs. The extractive performance using pyridinium-based ILs followed the orderand for the IL, the sulfur removal selectivity of sulfur compounds followed the order thiophene (TS) < benzothiophene (BT) < dibenzothiophene (DBT) under the same conditions. The pyridinium-based ILs would not contaminate the diesel due to their insolubility. On the other hand, diesel has a certain solubility in pyridinium-based ILs, varying from 0.49 wt % for [BPy][BF 4 ] to 1.97 wt % for [OPy][BF 4 ]. According to the results, [HPy][BF 4 ] and [OPy][BF 4 ] might be used as promising solvents for the extractive desulfurization of diesel.

The capacity of NH3 in PIL [Bim][NTf2] was up to 2.69 mol NH3 per mol IL under ambient conditions.