A series of well-crystallized nickel selenides, including NiSe2, Ni0.85Se,
and Ni3Se2 have been synthesized via a solvothermal technique. The single p
hases can be conveniently obtained under controlled conditions. Interesting
ly, the crystals of single phases as well as the mixtures obtained in selec
ted solvents own different morphologies. The solution synthetic route intro
duced in this paper may be applicable to a broad range of transition metal
chalcogenides with different morphologies.