Chemical synthesis and optical, structural, and surface characterization of InP-In2O3 quantum dots.

• InP-In 2 O 3 QDs are synthesized by a single-step chemical method without injection of hot precursors. • HR-TEM images show the synthesis of InP and In 2 O 3 QDs. • The InP and In 2 O 3 QDs size increases with the P(TMS) 3 concentration. • PL spectra reveal emission bands attributed to InP and In 2 O 3 QDs. • XPS confirms the formation of InP, In 2 O 3 and amorphous InPO x. InP-In 2 O 3 colloidal quantum dots (QDs) synthesized by a single-step chemical method without injection of hot precursors (one-pot) were investigated. Specifically, the effect of the tris(trimethylsilyl)phosphine, P(TMS) 3 , precursor concentration on the QDs properties was studied to effectively control the size and shape of the samples with a minimum size dispersion. The effect of the P(TMS) 3 precursor concentration on the optical, structural, chemical surface, and electronic properties of InP-In 2 O 3 QDs is discussed. The absorption spectra of InP-In 2 O 3 colloids, obtained by both UV–Vis spectrophotometry and photoacoustic spectroscopy, showed a red-shift in the high-energy regime as the concentration of the P(TMS) 3 increased. In addition, these results were used to determine the band-gap energy of the InP-In 2 O 3 nanoparticles, which changed between 2.0 and 2.9 eV. This was confirmed by Photoluminescence spectroscopy, where a broad-band emission displayed from 2.0 to 2.9 eV is associated with the excitonic transition of the InP and In 2 O 3 QDs. In 2 O 3 and InP QDs with diameters ranging approximately from 8 to 10 nm and 6 to 9 nm were respectively found by HR-TEM. The formation of the InP and In 2 O 3 phases was confirmed by X-ray Photoelectron Spectroscopy. [ABSTRACT FROM AUTHOR]