Coloring Tetrahedral Semiconductors: Synthesis and Photoluminescence Enhancement of Ternary II-III-VI Colloidal Nanocrystals.

Ternary tetrahedral II-III-VI semiconductors, where II is Zn or Cd, III In or Ga, and VI S, Se, or Te, are of interest in UV radiation detectors in medicine and space physics as well as CO photoreduction under visible light. We synthesize colloidal II-III-VI semiconductor nanocrystals from readily available precursors and ascertain their ternary nature by structural and spectroscopic methods, including Se solid-state NMR spectroscopy. The pyramidally shaped nanocrystals range between 2 and 12 nm and exhibit optical gaps of 2-3.

Designing complex PbSBrI chalcohalides: tunable emission semiconductors through halide-mixing.

Chalcohalides are desirable semiconducting materials due to their enhanced light-absorbing efficiency and stability compared to lead halide perovskites. However, unlike perovskites, tuning the optical properties of chalcohalides by mixing different halide ions into their structure remains to be explored. Here, we present an effective strategy for halide-alloying PbSBrI (1 ≤ ≤ 3) using a solution-phase approach and study the effect of halide-mixing on structural and optical properties.