Tadpole-Shaped AgInSe₂ Nanocrystals from a Single Molecular Precursor and its Nonlinear Optical Properties

Abstract

Orthorhombic tadpole-shaped AgInSe 2 nanocrystals have been synthesized from the single molecular precursor [(PPh 3 ) 2 AgIn(SeC{O}Ph) 4 ]. Reaction parameters such as temperature, surfactant concentration, and heating duration have been optimized to get monodispersed AgInSe 2 nanotadpoles. Severe stacking faults were observed in the crystal lattice of the tadpole nanostructure, which indicate that these AgInSe 2 nanotadpoles experience strain while the particles were grown in solution. A possible mechanism proposed involves disassociation of the precursor when dissolved in oleylamine and dodecanethiol solution, and the dissociated products further decomposed into Ag 2 Se nanocubes together with probably, indium-based decomposed products. In the extended heating process, these two react to form the AgInSe 2 tadpole-shaped nanoparticles. The obtained tadpole-shaped AgInSe 2 nanocrystals exhibit significant third-order nonlinear optical properties.