Facile synthesis of flake-like nickel disulfide nanocrystallites

Intrinsic giant magnetoresistance due to exchange-bias-type effects at the surface of single-crystalline NiS2 nanoflakes

“…Unlike other NiS 2 nanoflakes reported in the literature, which are prepared via chemical synthesis methods, mostly for water splitting applications, 26,27 our NiS 2 nanoflakes are single-crystalline because they are obtained from NiS 2 single crystals, from which they must retain certain physical properties. The NiS 2 nanoflakes reported in this study have a thickness ranging between ∼200 nm and 800 nm, which makes them about three orders of magnitude thinner than the thinnest NiS 2 single-crystalline samples reported to date, which were produced by mechanical polishing.…”

Phase Evolution, Polymorphism, and Catalytic Activity of Nickel Dichalcogenide Nanocrystals

“…Synthetically, nickel chalcogenides are most often prepared by solvothermal, hydrothermal, and sulfurization/selenization methods. ,,, A few synthetic methods employ single-source precursor decomposition − or chemical vapor deposition. , Solution-phase preparations of pyrite nickel diselenide particles have been reported. ,, In this work, we use nickel disulfide and diselenide nanocrystalssynthesized colloidallyto elucidate the effect of different reaction parametersprecursors, temperature, and timeon the evolution of nanocrystalline p -NiS 2 versus α-NiS, as well as on the evolution of pyrite- versus marcasite-NiSe 2 . Furthermore, we use computational methods to estimate the total energies of the two NiSe 2 polymorphs and use these calculations to explain our experimental observations.…”