Structure and magnetic properties of flower-like α-NiS nanostructures

▶ This method is environmentally friendly. ▶ Flower-like α-NiS nanostructure has been prepared by a facile one-step hydrothermal method successfully. ▶ The magnetic properties of flower-like α-NiS nanostructure have been studied. In this paper we report the structure and magnetic properties of flower-like α-NiS nanostructure prepared by a facile one-step hydrothermal method. The flowers consist of polycrystalline nanoflakes, and the nanoflakes are composed of single crystalline nanocrystals with an average size of about 15nm. The α-NiS flowers exhibit the transition from paramagnetism to ferromagnetism with the blocking temperature of about 12K. The field dependences of the magnetization prove that these flowers demonstrate a coexistence of antiferromagnetism and ferromagnetism at 5K, and exhibit a strong paramagnetic response at temperature higher than 100K.