No abstract

In this study, a gel polymer electrolyte (GPE) based on polymer ionic liquid (PIL) is used in a solvent-free and in a hybrid electrolyte configuration for Li-S batteries. Results obtained in the solvent-free configuration show a high discharge capacity in the first cycle and excellent coulombic efficiency during cycling. Capacity fading and polarization increase during cycling are explained based on the XPS and EIS measurements. The results of the present study are indicating that the increase of various internal resistance contributions and capacity fading are related with an accumulation of polysulfides in the GPE-PIL layer or/and on the surface of the lithium anode. Within a hybrid battery configuration, the thickness of the GPE-PIL layer is thinner, and the volume where polysulfides can be trapped is smaller. Such a configuration shows better cycling stability. The hybrid configuration outperforms cycling stability of the conventional configuration with a liquid electrolyte. This is explained by increased internal resistance in the convential configuration while the polarization in the first 100 cycles is constant in the hybrid configuration. Additionally, the hybrid configuration exhibits excellent C-rate performance.

Lignin, an aromatic polymer, offers interesting electroactive redox properties and abundant active functional groups.

Abstract2‐Arylpyridines are an important class of ligands for the synthesis of complexes with physical properties. We observed that the use of 3‐, 4‐ or 5‐bromo‐2‐chloropyridines allows the synthesis of a wide variety of heteroarylated 2‐arylpyridines by means of successive direct arylation and Suzuki coupling. For these two reactions, an air‐stable catalyst associated to a cheap and nontoxic base was employed as the catalyst. Moreover, a wide range of heteroarenes and functionalised arylboronic acids could be tolerated.