Aluminum‐sulfur (Al−S) chemistry is attractive for the development of next‐generation rechargeable battery systems. However, only a few reversible Al−S cells have been reported until now. This paper demonstrates that the use of an AlCl3/urea electrolyte in Al−S cells is a promising approach to improve the cycle life and reach a high discharge voltage plateau of ∼1.6–2.0 V. In contrast to the instability of sulfur in the conventional AlCl3/EMIC electrolyte, sulfur is chemically stable in the AlCl3/urea electrolyte, which allows better cell cycling stability. The Al−S cell delivers an initial capacity of ∼700 mAh gs−1 and maintains a capacity of up to ∼500 mAh gs−1 after 100 cycles.

Electrochemical cells with aluminum (Al) as the active material offer the benefits of high energy density, low cost, and high safety. Although several research groups have assembled rechargeable Al//M x O y (M = Mn, V, etc) cells with 2 m aqueous Al trifluoromethanesulfonate as an electrolyte and demonstrated the importance of the artificial solid electrolyte interphase (ASEI) on the Al anode for realizing high rechargeable capacity, the reactions of the Al anode in such cells remain underexplored. Herein, we investigate the effects of the ASEI on the charge/discharge cycling stability and activity of Al cells with the abovementioned aqueous electrolyte and reveal that this interphase provides chloride anions to induce the corrosion of Al rather than to support the transportation of Al3+ ions during charge/discharge. Regardless of the ASEI presence/absence, the main reactions at the Al anode during charge/discharge cycling are identified as oxidation and gas evolution, which suggests that the reduction of Al in the employed electrolyte is irreversible. The simple introduction of chloride anions (e.g., 0.15 m NaCl) into the electrolyte is shown to allow the realization of an Al//MnO2 cell with superior performance (discharge working voltage ≈ 1.5 V and specific capacity = 250 mA h/g). Thus, the present work unveils the mechanisms of reactions occurring at the Al anode of aqueous electrolyte Al cells to support their further development.

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Cysteine modified Ag nanoparticles were prepared in aqueous solution, via one-pot protocol, which were characterized by transmission electron microscopy (TEM), Fourier transform infrared (FT-IR) and ultraviolet-visible spectroscopy (UV-vis). The nanoparticles provided a simple and rapid strategy to detect histidine (His) visually with the help of Hg(2+) ions in solution. The colorimetric sensor allows a rapidly quantitative assay of histidine down to the concentration of 3 x 10(-5) M. The mechanism by which Hg(2+) ions can bind with both the cysteine modified Ag nanoparticles and His molecule through cooperative metal-ligand interactions is discussed.

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