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Au nanoparticles with anisotropic shape have drawn tremendous attention in the past two decades due to the unique physic-chemical properties originated from shape [1].Thereby,several methods controlling the shape of Au particles have been developed.In those methods,facile wet chemical route is the common method for generation of Au nanoparticles and the small functional groups such as Cl-,Br-,I- are prevalent groups for the shape control of Au nanoparticles [2-3].However,various types of amine groups (primary,secondary,tertiary and quaternary amines) for controlling Au particle shape,until now,has not been demonstrated,only the quaternary and tertiary amine groups had the molecular recognition ability and the quaternary amine group selective capped on the {111} facet and formed plate Au,while primary amine group without specific interaction of {111},{100} and {110} facets [4].In this work,the detail influence of amine groups in linear poly (ethyleneimine) (L-PEI),branched poly ethyleneimine (B-PEI) and urea on the shape control of Au particles have been investigated by adjusting the concentration of PEI and urea.The Au plates were obtained with lower concentration of PEI,while under higher concentration of PEI the spherical Au nanoparticles were generated.Furthermore,the size and yield of Au plates increased with the enhancing urea concentration.The results demonstrate that the selective adsorption of primary and secondary amine groups on specific facets is the crucial role for the formation of plates and spherical Au particles.In particular,primary and secondary amine groups in PEI adsorbed effectively on {111} facet for the formation of Au plates.However,the adsorption ability of primary amine group on {111} facet is stronger than that of secondary amine group.Furthermore,the primary amine group in urea only played a capping role in formation of plate with well-defined shape as same as the primary amine in PEI.Importantly,the primary and secondary amine groups in PEI not only acted as capping groups for the shape controlling but also acted as reducing groups for generation of Au particles.This improved insight into the specific roles of the amine groups for morphology controlling is expected to elucidate the formation mechanism of Au plates and the tunable morphology.