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Abstract Aqueous electrolytes are promising in large-scale energy storage applications due to intrinsic low toxicity, non-flammability, high ion conductivity, and low cost. However, pure water’s narrow electrochemical stability window (ESW) limits the energy density of aqueous rechargeable batteries. Water-in-salt electrolytes (WiSE) proposal has expanded the ESW to over 3 V by changing electrolyte solvation structure. The limited solubility and WIS electrolyte crystallization have been persistent concerns for imide-based lithium salts. Asymmetric lithium salts compensate for the above flaws. However, studying the solvation structure of asymmetric salt aqueous electrolytes is rare. Here, we applied small-angle x-ray scattering (SAXS) and Raman spectroscope to reveal the solvation structure of imide-based asymmetric lithium salts. The SAXS spectra show the blue shifts of the lowerqpeak with decreased intensity as the increasing of concentration, indicating a decrease in the average distance between solvated anions. Significantly, an exponential decrease in the d-spacing as a function of concentration was observed. In addition, we also applied the Raman spectroscopy technique to study the evolutions of solvent-separated ion pairs (SSIPs), contacted ion pairs (CIPs), and aggregate ions (AGGs) in the solvation structure of asymmetric salt solutions. 

In this work, a Pt catalyst supported on an equimolar Al 2 O 3 –CeO 2 binary oxide (Pt–Al–Ce) was prepared and applied in photo-thermo-chemical dry reforming of methane (DRM) driven by concentrated solar irradiation. It was found that the Pt–Al–Ce catalyst showed good stability in DRM reactions and significant enhancements in H 2 and CO production rates compared with Pt/CeO 2 (Pt–Ce) and Pt/Al 2 O 3 (Pt–Al) catalysts. At a reaction temperature of 700 °C under 30-sun equivalent solar irradiation, the Pt–Al–Ce catalyst exhibits a stable DRM catalytic performance at a H 2 production rate of 657 mmol g −1 h −1 and a CO production rate of 666 mmol g −1 h −1 , with the H 2 /CO ratio almost equal to unity. These production rates and the H 2 /CO ratio were significantly higher than those obtained in the dark at the same temperature. The light irradiation was found to induce photocatalytic activities on Pt–Al–Ce and reduce the reaction activation energy. In situ diffuse reflectance infrared Fourier transform spectroscopy ( in situ DRIFTS) was applied to identify the active intermediates in the photo-thermo-chemical DRM process, which were bidentate/monodentate carbonate, absorbed CO on Pt, and formate. The benefits of the binary Al 2 O 3 –CeO 2 substrate could be ascribed to Al 2 O 3 promoting methane dissociation while CeO 2 stabilized and eliminated possible coke formation, leading to high catalytic DRM activity and stability. 

Abstract Carbon–carbon bond cleavage reactions, adapted to deconstruct aliphatic hydrocarbon polymers and recover the intrinsic energy and carbon value in plastic waste, have typically been catalysed by metal nanoparticles or air-sensitive organometallics. Metal oxides that serve as supports for these catalysts are typically considered to be inert. Here we show that Earth-abundant, non-reducible zirconia catalyses the hydrogenolysis of polyolefins with activity rivalling that of precious metal nanoparticles. To harness this unusual reactivity, our catalytic architecture localizes ultrasmall amorphous zirconia nanoparticles between two fused platelets of mesoporous silica. Macromolecules translocate from bulk through radial mesopores to the highly active zirconia particles, where the chains undergo selective hydrogenolytic cleavage into a narrow, C 18 -centred distribution. Calculations indicated that C–H bond heterolysis across a Zr–O bond of a Zr(O) 2 adatom model for unsaturated surface sites gives a zirconium hydrocarbyl, which cleaves a C–C bond via β-alkyl elimination.