Influence of the choice of indium precursor and ligand on the synthesis of InP nanocrystals

Abstract

Well-crystallized InP nanocrystals with particle diameters ranging from 2 to 5.5 nm were prepared via the reaction between tris(trimethylsilyl)phosphine and different indium precursors. The classic TOP/TOPO reaction medium was replaced by the weakly coordinating solvent diphenylether, which contained a strongly coordinating ligand at low concentrations. Different phosphine oxides, phosphines, phosphates, phosphites and phosphonates were used as ligands and their influence on the growth of InP nanocrystals was studied. The synthesis procedure allows to prepare crystalline InP quantum dots (QDs) at temperatures as low as 150 degrees C and within short reaction times. The final size of the InP QDs is remarkably independent of the choice of ligand and indium precursor.