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Ternary deep eutectic solvents (DES) comprising choline chloride (ChCl), glycerol (Gly) and ethanolamine (MEA) with different molar ratios were prepared. The CO2 absorption ability of the ternary DES was investigated at room temperature and under atmospheric pressure. Among four ternary DES samples prepared with different molar ratios, a ChCl-Gly-MEA (1:1:10) ternary DES was found to absorb the most CO2 at a capacity of 0.18 g CO2 (DES per gram) at 298 K and 101.3 kPa. The experimental results showed that the CO2 absorption capacity of ChCl-Gly-MEA (1:1:10) ternary DES increased with an increase in gas flow rate and a decrease in water content. The gas flow rate improved the mass transfer efficiency of CO2 in the ternary DES system, and shortened the time required for CO2 absorption to reach equilibrium. However, the addition of water could weaken the hydrogen bonding interaction among the three components in the DES system. Results from Fourier transform infrared (FT-IR) and nuclear magnetic resonance (NMR) spectroscopy indicated that CO2 interacted with the amino groups in DES to form carbamates. The absorption of CO2 by ChCl-Gly-MEA underwent both physical and chemical absorption, and the chemical absorption was significantly enhanced by the addition of MEA. A recovery experiment showed that no obvious loss in CO2 absorption was detected after five absorption/desorption cycles with an absorption rate of 97.3% being retained. [ABSTRACT FROM AUTHOR]

Using first-principles calculations, we have systematically investigated the adsorption and diffusion behavior of Li in MoO 3 bulk, on MoO 3 (010) surface and in MoO 3 /graphene composite. Our results indicate that, in case of MoO 3 bulk, Li diffusion barriers in the interlayer and intralayer spaces are 0.55 eV and 0.58 eV respectively, which are too high to warrant fast Lithium-ion charge/discharge processes. While on MoO 3 (010) surface, Li exhibits a diffusion barrier as low as 0.07 eV which guarantees an extremely fast Li diffusion rate during charge/discharge cycling. However, in MoO 3 /graphene monolayer, Li diffusion barrier is at the same level as that on MoO 3 (010) surface, which also ensures a very rapid Li charge/discharge rate. The rapid Li charge/discharge rate in this system originates from the removal of the upper dangling O1 atoms which hinder the Li diffusion on the lower MoO 3 layer. Besides this, due to the interaction between Li and graphene, the Li average binding energy increases to 0.14 eV compared to its value on MoO 3 (010) surface which contributes to a higher voltage. Additionally, the increased ratio of surface area provides more space for Li storage and the capacity of MoO 3 /graphene composite increases up to 279.2 mAhg −1 . The last but not the least, due to the high conductivity of graphene, the conductivity of MoO 3 /graphene composite enhances greatly which is beneficial for electrode materials. In the light of present results, MoO 3 /graphene composite exhibits higher voltage, good conductivity, large Li capacity and very rapid Li charge/discharge rate, which prove it as a promising cathode material for high-performance lithium-ion batteries (LIBs). [ABSTRACT FROM AUTHOR]