Stepwise Growth of Decahedral and Icosahedral Silver Nanocrystals in DMF

Silver nanocrystals were synthesized by reducing AgNO3 in N,N'-dimethylformamide (DMF) solution. Besides decahedral and icosahedral nanoparticles, a series of their intermediate particles. which consist of it combination of two and more tetrahedra. are obtained. It wits found that decahedral and icosahedral nanoparticles are not Formed through assembling of tetrahedra formed separately but produced through the stepwise growth of tetrahedral units On specific facets in DMF. A simple combination model of tetrahedral units Suggested that the growth position of the fourth tetrahedral unit determines whether it decahedron or icosahedron is finally Produced. tit the formation of icosahedron the crystal growth occurs inside of decahedral units. No further growth from decahedron to icosahedron was observed, indicating that there is it large energy barrier for the addition of a tetrahedron unit to it decahedron, Our study gives new information oil the stepwise growth mechanism of decahedra and icosahedra in DMF solution.