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In this work, a new class of single Li-ion polyelectrolyte (SLIP) based on a polyurea matrix was developed from triazolate salt and diisocyanates with an aliphatic or aromatic moiety. The structure and chemical information were checked by Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy analyses. The aggregate structure, thermal stability, phase behavior and morphology were examined via X-ray diffraction, thermogravimetric analysis, differential scanning calorimetry and scanning electron microscopy, respectively. It was found that the obtained SLIPs were disordered pore materials with amorphous structures and high stability, and the influence of varied isocyanate monomers on their properties was associated with hydrogen bonding derived from urea linkage. Furthermore, the electrochemical properties for the SLIPs absorbing dimethyl sulfoxide were determined by cyclic voltammetry, linear sweep voltammetry and electrochemical impedance spectroscopy, and the results showed that the electrolytes could endure an oxidation potential up to 4.2 V (vs. Li+/Li) and exhibited a practicable conductivity (10−4 S cm−1) at 30 °C. The cycling performance for an Li|Li cell was also tested preliminarily. The obtained results indicated that the developed SLIPs could be used as potential polyelectrolytes in lithium batteries. [ABSTRACT FROM AUTHOR]

Nano CuO/ZSM-5 zeolite was prepared and used as a catalyst for dehydration of 1,4-butanediol (BDO) to tetrahydrofuran (THF) in liquid-phase. It was found that the 4.6 wt% CuO/ZSM-5 displayed good catalytic performance, and nearly 100% of BDO conversion and more than 99% of THF selectivity could be achieved by a rotary evaporator reactor at 170 °C under the atmospheric pressure. With such mild reaction conditions, 2400 g BDO could be converted to THF over 1 g catalyst under semi-continuous operation. Characterizations with X-ray diffraction (XRD), temperature-programmed reduction (TPR), NH3-temperature programmed desorption (TPD), X-ray photoelectron spectroscopy (XPS), transmission electron microscope (TEM) and Brunauer-Emmett-Teller (BET) over fresh and used 4.6 wt% CuO/ZSM-5 were conducted. Based on the results of the characterization and catalytic performance of 4.6 wt% CuO/ZSM-5, it can be conjectured that the formed 1-3 nm CuO nanoparticles, suitable acidity of the catalyst due to the synergic interaction of CuO and ZSM-5 support promoted the dehydration of BDO to THF. [ABSTRACT FROM AUTHOR]