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Ionic liquids (ILs) and deep eutectic solvents (DESs) are regarded as two types of novel solvents with high tunability, which exist in the liquid state in a wide temperature range. The sustainability of ILs and DESs enable their wide utilization as solvents, absorbents, electrolytes, surfactants, catalysts, lubricants and photosensitizers. Additionally, the stability of ILs and DESs is necessary for their application in industry. However, not all ILs and DESs are sufficiently stable. Herein, we present a comprehensive and systematic review on the thermal, chemical, electrochemical, radiolytic and biological stability of ILs and DESs. This can provide a guide for the better design of ILs and DESs with higher stability for industrial applications. [ABSTRACT FROM AUTHOR]

The concept of CO2 switchable deep eutectic solvents (DESs) was proposed and a series of CO2 switchable imidazole-based deep eutectic solvents (DESs) was designed. The CO2 switch mechanism was investigated and the system was used for easy emulsion separation of olive oil from DESs. The benign CO2 switchable DESs have great potential applications in dissolution and easy separation. [ABSTRACT FROM AUTHOR]

We for the first time have found that PEG-based DESs could volatilize at room temperature and atmospheric pressure. The mass loss from long-term evaporation of PEG-based DESs at 298.15 K for 1000 min could reach as high as 30.5% mass loss, ca. 6 times that of short-term evaporation (5.1% mass loss). Generally, the vaporization enthalpy of PEG-based DESs is found to lie between that of common organic solvents and that of ionic liquids, while some PEG-based DESs could be more volatile than common organic solvents. The evaporation of PEG-based DESs could be ascribed to their volatile constituents; however, the evaporation rate of each constituent is found to be very different. This is the first discovery of the higher volatility of PEG-based DESs at room temperature and atmospheric pressure. [ABSTRACT FROM AUTHOR]

Polyethylene glycol (PEG)-based deep eutectic solvents (DESs) emerge as a new class of DESs and have attracted great attention. Surface tension and surface thermodynamic properties are key physiochemical parameters for better utilization of PEG-based DESs. However, surface-related physical parameters of PEG-based DESs have not been investigated. Here, comprehensive investigation on surface tension, surface thermodynamic properties and the corresponding factors (e.g., hydrogen-bonding donor, component type, temperature, water, organic solvent, inorganic salt solution, molecular weight of PEG, concentration and mole ratio) were carried out. Moreover, PEG-based DESs dissociation in water was investigated and it was found that DESs would almost dissociate in water at the concentration of around the turning point at x H2O = 0.9, however, no such a turning point of dissociation would exist in other solvents. Surface tension and surface thermodynamic properties of PEG-based deep eutectic solvents are for the first time investigated. Unlabelled Image • Factors affecting surface tension of PEG-based DESs are studied. • Surface thermodynamic properties are firstly studied. • Water dissociation in PEG-based DESs is firstly observed at x H2O = 0.9. [ABSTRACT FROM AUTHOR]

[Display omitted] • Superlong supercooling solvents (SSSs) are firstly proposed as the new green solvents. • SSSs are the alternative green solvents to ionic liquids and deep eutectic solvents. • Superlong supercooling solvents (SSSs) are firstly proposed as the new generation of green solvents for LIBs recycling. • SSSs show high Co leaching efficiency from lithium-ion batteries cathode. • The leaching process by SSSs is mild, efficient and green. Water, supercritical fluids, ionic liquids and deep eutectic solvents (DESs) have been considered as green solvents for many years. The demand of green and sustainable development requires the search of novel green solvents. Some of the reported DESs might be not be the real DESs because we observe that these so-called reported liquid DESs become solid after exposure to the room temperature for many hours or days. Here, we for the first time propose a new concept of green solvents, superlong supercooling solvents (SSSs), as the green alternatives to water, supercritical fluids, ionic liquids and DESs. SSSs are the metastable liquid solvents either single component or multiple components due to the superlong supercooling effect at the temperature around or a little higher than room temperature. SSSs should condense after a superlong time; however, SSSs could be used as the green solvents before the condensation due to the superlong supercooling. Typical application example of SSSs is that SSSs could leach nearly 100% valuable metals from lithium-ion batteries cathode at low temperature, which is much higher than that by reported DESs and ILs at the same conditions. The new concept of SSSs would be very helpful for expanding the area of green solvents and green chemistry for building a greener world. [ABSTRACT FROM AUTHOR]

Abstract: Large-size and high-quality anthracene single crystals have been grown by a solution technique. The size of crystals reaches 2.2cm and the crystals with rhombic plane have been obtained for the first time. FTIR and Raman analysis indicate that the crystals did not incorporate the solvent at the detection level. XRD analysis indicates that the anthracene single crystals have good quality. The morphology of surface and transect of anthracene single crystals was observed by optical microscope, atomic force microscope (AFM), and scanning electron microscope (SEM). Anthracene monolayers and the array of large straight steps were observed on the surface of anthracene single crystals. Layer-like structure was also observed in the interior of single crystals. All results indicate that the growth mechanism of anthracene single crystals is a two-dimensional nucleation—elementary steps—large straight steps—layer-by-layer periods growth. [Copyright &y& Elsevier]