Inclusion Compounds

Low-temperature resistance minimum in non-superconducting 3R-Nb1+xS2and 3R-GaxNbS2

“…In 1T-TaS 2 a mere 50 ppm of isoelectronic Nb impurities were observed to destroy the long-range phase coherence of the commensurate CDW and completely suppress the associated metal-insulator (MI) transition [4]. On intercalation, T c for Ta compounds increases from <1 K to 5 K while it is lowered for Nb [5][6][7][8][9]. For selfintercalated 2H-Nb 1.05 Se 2 , T c was suppressed below 2.2 K [5], while 2H-NbSe 2 (EDA) 1/4 showed no superconductivity but a resistance minimum at ∼25 K [7].…”

Alkaline Metal Intercalates of VSe2 by Electrochemical Intercalation

“…These superconducting properties could be changed substantially by intercalation with different types of ions and molecules, providing an ideal playground for insights into the superconducting state. [17,32,33,2,34,35] This work is the first comprehensive report on the electrochemical intercalation of VSe 2 with the whole series of the alkaline metals in an aqueous environment. The new structures are analyzed by powder X-ray diffraction.…”

“…[13][14][15] This concept expanded quickly, regarding the used TMDs, as well as the used methods. [16][17][18] Initially, further chemical methods, e. g. the intercalation with n-buthyllithium were reported, which is also the first chemical method which was employed to intercalate VSe 2 . [19,20] Subsequently, in 1974 several groups reported the first electrochemical intercalation of TMDs.…”

“…However, only in 1959 the possibility of a post‐synthetic intercalation of this type of material was realized by Rüdorff by intercalating MoS 2 and WS 2 with the alkaline metals in liquid ammonia [13–15] . This concept expanded quickly, regarding the used TMDs, as well as the used methods [16–18] . Initially, further chemical methods, e. g. the intercalation with n‐buthyllithium were reported, which is also the first chemical method which was employed to intercalate VSe 2 [19,20] .…”

“…While this can be beneficial when it comes to applications as electrode materials in batteries, the latter is particularly of interest, as many of the TMDs exhibit unusual physical properties such as superconductivity. These superconducting properties could be changed substantially by intercalation with different types of ions and molecules, providing an ideal playground for insights into the superconducting state [17,32,33,2,34,35] …”