Single crystal silver nanosheets have been synthesized in water without any organic surfactant or polymer to direct the growth of nanoparticles. The nanosheets were formed through a modified silver mirror reaction in which silver ammonia ions were reduced to metallic silver by glucose and an inorganic species, aluminum nitrate, was introduced to the system. Thermodynamic calculation demonstrates that the aluminum hydroxide generated in situ from aluminum nitrate plays a key role in the formation of silver nanosheets. (c) 2005 Elsevier B.V. All rights reserved.