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In this work, the blends of 1-hydroxyethyl-3-methylimidazolium glycine ([C 2 OHmim][Gly]) synthesized by our laboratory and N-methyldiethanolamine (MDEA) in aqueous solution were prepared for CO 2 capture, and the maximum absorption performance of the blends was obtained at the mole ratio of 8:2 of MDEA/[C 2 OHmim][Gly] with a total concentration of 1.0 mol L −1 . CO 2 loading of the blended absorbent was less adversely influenced by the temperature and O 2 concentration than that of MDEA aqueous, and it had a good performance in regeneration ability. The reaction mechanism of the CO 2 absorption in MDEA/[C 2 OHmim][Gly] was investigated by 13 C nuclear magnetic resonance. CO 2 first reacted with [C 2 OHmim][Gly] to form carbamate, and then carbamate promoted the reaction between CO 2 and MDEA, which could be described as a shuttle mechanism. The kinetics of CO 2 absorption was investigated in a double stirred-cell absorber at different temperatures, and some important kinetic parameters were obtained, such as the reaction rate constant (k 2 ) and the overall rate constant (k ov ). Experimental results indicated that the addition of [C 2 OHmim][Gly] enhanced CO 2 absorption of MDEA under low CO 2 partial pressure, which could improve the application of MDEA in industry.

Highlights A creative cooperative strategy involving silk fibroin/sericin is proposed for stabilizing high-performance flexible Li–S full batteries with a limited Li excess of 90% by simultaneously inhibiting lithium dendrites, adsorbing liquid polysulfides, and anchoring solid lithium sulfides. Such fabric Li–S full batteries offer high volumetric energy density (457.2 Wh L −1 ), high-capacity retention (99.8% per cycle), and remarkable bending capability (6000 flexing cycles at a small radius of 5 mm). Abstract Lithium–sulfur batteries are highly appealing as high-energy power systems and hold great application prospects for flexible and wearable electronics. However, the easy formation of lithium dendrites, shuttle effect of dissolved polysulfides, random deposition of insulating lithium sulfides, and poor mechanical flexibility of both electrodes seriously restrict the utilization of lithium and stabilities of lithium and sulfur for practical applications. Herein, we present a cooperative strategy employing silk fibroin/sericin to stabilize flexible lithium–sulfur full batteries by simultaneously inhibiting lithium dendrites, adsorbing liquid polysulfides, and anchoring solid lithium sulfides. Benefiting from the abundant nitrogen- and oxygen-containing functional groups, the carbonized fibroin fabric serves as a lithiophilic fabric host for stabilizing the lithium anode, while the carbonized fibroin fabric and the extracted sericin are used as sulfiphilic hosts and adhesive binders, respectively, for stabilizing the sulfur cathode. Consequently, the assembled Li–S full battery provided a high areal capacity (5.6 mAh cm −2 ), limited lithium excess (90%), a high volumetric energy density (457.2 Wh L −1 ), high-capacity retention (99.8% per cycle), and remarkable bending capability (6000 flexing cycles at a small radius of 5 mm). Supplementary Information The online version contains supplementary material available at 10.1007/s40820-021-00609-3.

The lithium (Li)‐metal anode offers a promising solution for high‐energy‐density lithium‐metal batteries (LMBs). However, the significant volume expansion of the Li metal during charging results in poor cycling stability as a result of the dendritic deposition and broken solid electrolyte interphase. Herein, a facile one‐step roll‐to‐roll fabrication of a zero‐volume‐expansion Li‐metal‐composite anode (zeroVE‐Li) is proposed to realize high‐energy‐density LMBs with outstanding electrochemical and mechanical stability. The zeroVE‐Li possesses a sandwich‐like trilayer structure, which consists of an upper electron‐insulating layer and a bottom lithiophilic layer that synergistically guides the Li deposition from the bottom up, and a middle porous layer that eliminates volume expansion. This sandwich structure eliminates dendrite formation, prevents volume change during cycling, and provides outstanding flexibility to the Li‐metal anode even at a practical areal capacity over 3.0 mAh cm−2. Pairing zeroVE‐Li with a commercial NMC811 or LCO cathode, flexible LMBs that offer a record‐breaking figure of merit (FOM, 45.6), large whole‐cell energy density (375 Wh L−1, based on the volume of the anode, separator, cathode, and package), high‐capacity retention (> 99.8% per cycle), and remarkable mechanical robustness under practical conditions are demonstrated.

In this work, the aqueous solutions of 1-hydroxyethyl-3-methylimidazolium lysine ([C2OHmim]­[Lys]) and methyldiethanolamine (MDEA) were developed to obtain an efficient absorbent for CO2 capture. The absorption performance, regeneration performance, reaction mechanism, and kinetic study of the blends were investigated. It was found that, for the blended absorbents, a molar ratio of 8:2 of MDEA/[C2OHmim]­[Lys] was the optimum ratio based on the absorption rate, absorption capacity, and other factors. The CO2 absorption capacity of the blends is 0.75 mol of CO2/mol of ionic liquid, and the absorption rate was higher than that of the aqueous MDEA solution. The regeneration efficiency of the blends was 93% after the third absorption generation cycle, which was higher than the aqueous solutions of 1 mol/L MDEA (88%) or 1 mol/L [C2OHmim]­[Lys] (88%) under the same conditions, indicating a better regeneration performance of the blends. The reaction mechanism and kinetic study of the CO2 absorption into the blends were investigated by 13C nuclear magnetic resonance and a double stirred-cell absorber, respectively. [C2OHmim]­[Lys] in aqueous solution first formed carbamate with CO2, and the next step was hydrolysis of MDEA and partial carbamate, with the production of bicarbonate. It also found that the influence of the temperature in the CO2 absorption was different in the two steps. Also, [C2OHmim]­[Lys] could promote the hydration reaction of MDEA and CO2 according to the chemical mechanism and kinetic study. The kinetic region was considered to be a fast pseudo-first-order reaction, and the activation energy of the blends was 40.0 kJ mol–1.