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Increasing the liquid content has been recognized as an effective strategy to enhance the Li+ conductivity and electrode compatibility of gel electrolytes for lithium-metal batteries (LMBs). However, a low gelator content reduces the mechanical strength of gels. Herein, a mechanically stable gel electrolyte comprising 7 wt% methylcellulose (MC), 3 wt% 12-hydroxyoctadecanoic acid (12-HOA), and 90 wt% concentrated sulfone electrolyte (CSE) was developed. Because of its high electrolyte uptake, the MC/12-HOA gel electrolyte exhibits an ionic conductivity of 0.25 mS cm−1, which is similar to that of the neat CSE, and a Li+ transference number of 0.57, which is even higher than that of the CSE. Abundant ether groups on MC and hydroxyl groups on 12-HOA can strongly immobilize TFSI−via a hydrogen bond, endowing the MC/12-HOA gel with an elastic modulus of 10 MPa enough to form an 80 μm – thick self-supporting film and suppress Li dendrite growth. Additionally, a reversible gel–sol transition occurs in the MC/12-HOA gel at 329–331 K, which can be utilized to promote electrode wetting and seal the damages of electrolytes. As a result, the MC/12-HOA gel electrolyte displays reliable safety, practical flexibility, and suitable electrochemical performance in both the Li‖LiFePO4 and Li‖LiNi0.8Co0.1Mn0.1O2 cells, suggesting the great promise of the MC/12-HOA scaffold in gel electrolytes with different solvents for a wide range of applications in flexible devices. [ABSTRACT FROM AUTHOR]

Pervasive intrinsic defects have a significant impact on the electrocatalytic activity of carbon materials, but previous research has focused on the effects of topological structures exclusively. Herein, a compelling demonstration of the pivotal role played by the positions and spatial arrangement of intrinsic defects in determining their efficacy for electrochemical CO2 reduction (ECR) is presented. Theoretical calculations reveal a substantial reduction in energy barriers for *COOH formation at intrinsic defects positioned along the edges while hindering the transformation of *COOH to *CO in the ECR process. To address this issue, a sea urchin‐like nanocarbon (F1100) is designed, which provides adjacent intrinsic defects located in V‐type arranged carbon nanorods. The angulated edge intrinsic defects facilitate the bridge adsorption of carbon monoxide (CO), as confirmed by in situ attenuated total reflection surface‐enhanced infrared absorption spectroscopy, thereby enhancing the specific activity of ECR on intrinsic carbon defects. In a 0.1 m potassium bicarbonate (KHCO3) solution, F1100 achieves a FECO of 95.0%, while in an ionic liquids‐based electrolyte, a current density of 90.0 mA cm−2 is obtained with nearly complete conversion of CO2 to CO in an H‐type cell. [ABSTRACT FROM AUTHOR]

High-purity ethylene production from CO2 electroreduction (CO2RR) is a coveted, yet arduous feat because the product stream comprises a blend of unreacted CO2, H2, and other off-target CO2 reduction products. Here we present an indirect reduction strategy for CO2-to-ethylene conversion, one that employs 2-bromoethanol (Br-EO) as a mediator. Br-EO is initially generated from CO2RR and subsequently undergoes reduction to ethylene without the need for energy-intensive separation steps. The optimized AC-Ag/C catalyst with Cl incorporation reduces the energy barrier of the debromination step during Br-EO reduction, and accelerates the mass-transfer process, delivering a 4-fold decrease of the relaxation time constant. Resultantly, AC-Ag/C achieved a FEethylene of over 95.0 ± 0.36% at a low potential of −0.08 V versus reversible hydrogen electrode (RHE) in an H-type cell with 0.5 M KCl electrolyte, alongside a near 100% selectivity within the range of −0.38 to −0.58 V versus RHE. Through this indirect strategy, the average ethylene purity within 6-hour electrolysis was 98.00 ± 1.45 wt%, at −0.48 V (vs RHE) from the neutralized electrolyte after CO2 reduction over the Cu/Cu2O catalyst in a flow-cell. Producing high-purity ethylene from direct CO2 electroreduction is challenging due to unwanted byproducts and unreacted CO2. Here, authors introduce an indirect method using 2-bromoethanol as a mediator, which reduces to ethylene with near-unity selectivity over an Ag catalyst. [ABSTRACT FROM AUTHOR]

Electrochromic devices built with ionogel electrolytes are seen as a pivotal step toward the future of quasi‐solid electrochromic devices, due to their striking properties like exceptional safety and high ionic conductivity. Yet, the poor mechanical strength of electrolyte of these devices remains a constraint that hampers their advancement. As a resolution, this research explores the use of a robust, transparent ionogel electrolyte, which is designed using an in situ microphase separation strategy. The ionogels are highly transparent and robust and exhibit excellent physicochemical stability, including a wide electrochemical window and high temperature tolerance. Benefitting from these properties, a high‐performance electrochromic device is fabricated through in situ polymerization with the ionogels, PPRODOT as the electrochromic layer, and PEDOT: PSS as the ion storage layer, achieving high transmittance contrast (43.1%), fast response (1/1.7 s), high coloring efficiency (1296.4 cm2 C−1), and excellent cycling endurance (>99.9% retention after 2000 cycles). In addition, using ITO‐poly(ethylene terephthalate) as flexible substrates, a deformable electrochromic device displaying high stability is realized, highlighting the potential use in functional wearables. [ABSTRACT FROM AUTHOR]