Water-Soluble Alumina-Coated Indium Phosphide Core-Shell Quantum Dots with Efficient Deep-Red Emission Beyond 700 nm.

Solution-processed colloidal III-V semiconductor-based quantum dots (QDs) represent promising and environmentally-friendly alternatives to Cd-based QDs in the realms of optoelectronics and biological applications. While InP-based core-shell QDs have demonstrated efficient light-emitting diode (LED) performance in the visible region, achieving deep-red emission (above 700 nm) with a narrow linewidth has proven challenging. Herein, the study presents a novel strategy for synthesizing InP/ZnSe/ZnS core-shell-shell QDs tailored for emission in the first biological transparency window.

Narrow Near-Infrared Emission from InP QDs Synthesized with Indium(I) Halides and Aminophosphine.

Nonpyrophoric aminophosphines reacted with indium(III) halides in the presence of zinc chloride have emerged as promising phosphorus precursors in the synthesis of colloidal indium phosphide (InP) quantum dots (QDs). Nonetheless, due to the required P/In ratio of 4:1, it remains challenging to prepare large-sized (>5 nm), near-infrared absorbing/emitting InP QDs using this synthetic scheme. Furthermore, the addition of zinc chloride leads to structural disorder and the formation of shallow trap states inducing spectral broadening.