Ag-Ni bi-metal nanocrystals were prepared by a novel Solution method, in which ethanol was first taken as a green solvent with no use of any external toxic reducing agents. The as-prepared bi-metal nanocrystals were spherical and Constructed by an aggregation of tiny crystals with particle size of about 12 nm. Infrared data indicated that the surfaces of the as-prepared nanocrystals were free of organic contaminants. The obtained bi-metal nanocrystals showed great potential as the additive in promoting the decomposition of ammonium perchlorate (AP), the key component of composite solid propellants. They were also initiated as the anode material of solid oxide fuel cells (SOFCs) which showed a maximum power density of 52.34 mW cm(-2) for single cell at 800 C. (C) 2008 Elsevier B.V. All rights reserved.