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Ion selectivity of nanoporous graphene membranes is of great importance in separation technologies including ion sieving and seawater desalination. In this study, we put forward a method to produce...

Polythiophene is considered as an effective dry adhesive and is promising to be a conductive adhesive due to its excellent properties. Here, we used steered molecular dynamics to investigate the interfacial strength between polythiophene and various semiconductors with similar structures including silicon, silicon carbide, and diamond. Energy decomposition was done to have a detailed insight into the adhesive mechanism. Particularly, we laid stress on the entropy difference of the polythiophene chain in different systems. Van der Waals interaction and electrostatic interaction both positively contributed to the adhesion between polythiophene and semiconductors, while the entropy change of polythiophene, including vibrational entropy change and conformational entropy change, weakened the adhesion to some extent. Our results indicated that the combined effect of these three factors made the adhesion between polythiophene and silicon carbide the strongest among the systems we studied. Additionally, it was found that such adhesion was scarcely influenced by temperature. This simple polythiophene-semiconductor interfacial study can help optimize the choice of the semiconductor when applying the polythiophene adhesive.

The electrochemical intercalation of metal ions into layered materials is a useful strategy to reversibly tune thermal-transport properties, but the fundamental mechanisms are not well understood. In this study, we systematically investigated the effects of lithium-ion concentrations on the anisotropic thermal conductivity of intercalated graphite by molecular-dynamics simulations and a continuum-mechanics method. It was found that the in-plane thermal conductivity rapidly decreased to 34.3% of that of graphite in the same direction when the lithium-ion concentration increases to 0.1667. However, the cross-plane thermal conductivity first decreased to 23.7% of that of the graphite. Then, it surprisingly recovered to a thermal conductivity even higher than that of graphite when the lithium-ion concentration increased further. These two different trends and thermal-conductivity anisotropies were explained by extracting the phonon lifetimes and elastic constants of intercalated graphites with various lithium...