First-principles approach to the first step of metal–phosphine bond formation to synthesize alloyed quantum dots using dissimilar metal precursors

Abstract

InP-based quantum dots are promising candidates as Cd-free quantum dots; however, they require sharper fluorescence to satisfy the next-generation display standard. For this purpose, a deeper understanding of the crystal growth scheme and well-designed organometallic precursors are needed. Density functional theory calculations were used to find the activation barriers for the initial reaction of Zn, Ga, and In precursors with tris(trimethylsilyl)phosphine, and differences in reactivity between dissimilar metal precursors were revealed. The coordinations of the P precursor to Zn, In, and Ga precursors were found to differ significantly, depending on the coordination number and the ionic radius, and these results were consistent with reports that found that InZnP can be alloyed, but InGaP is not easily alloyed. The activation energies become close to each other when using thiol ligands with less steric hindrance in monodentate ligands. These results will lead to achieving precise composition control and great luminescence properties.