Amino-As-Based Synthesis of Near-Infrared Emitting InAs-Based Quantum Dots

Colloidal quantum dots (QDs) that absorb and emit in the infrared (IR) region have gained significant interest as cost-effective active materials for future consumer market optoelectronic applications. Among IR materials, InAs QDs have emerged as the most promising candidates due to their tunable bandgap, which can be adjusted from the visible to the IR range, and their compliance with the European “Restriction of Hazardous Substances” directives. Although the first reported colloidal synthesis dates back to the 1990s, the use of an expensive and pyrophoric As precursor, namely trimethylsilyl arsine, limited the development of such QDs. In recent years, the discovery of a cheap and promising alternative As precursor, tris(dimethylamino)arsine (amino-As), has opened up new synthesis avenues for InAs QDs. The main current challenge is to improve the optical performance of amino-As-based InAs QDs in order to achieve tunable photoluminescence (PL) with high quantum yields (QY).<br/>In this presentation, we will illustrate our recent studies on InAs QDs synthesized with amino-As, including 1) the impact of using ZnCl₂ as an additive and the effect of surfactants on InAs QDs;[1] 2) the development of the InAs@ZnSe core@shell system, focusing on controlling the interlayer between InAs and ZnSe, as well as the growth of an additional buffer interlayer or in-situ formation of the interlayer to improve their optical performance; [1,2] and 3) the fabrication of optoelectronic device utilizing these InAs@ZnSe QDs as the active NIR layer, including light-emitting diodes (LEDs) and photodetectors. [3]<br/><br/>References<br/>[1] D. Zhu <i>et al.</i>, ZnCl₂ Mediated Synthesis of InAs Nanocrystals with Aminoarsine. <i>J. Am. Chem. Soc.</i> 2022, <b>144</b>, 10515-10523.<br/>[2] D. Zhu et al., Boosting the Photoluminescence Efficiency of InAs Nanocrystals Synthesized with Aminoarsine via a ZnSe Thick-Shell Overgrowth. <i>Adv. Mater.</i> 2023, <b>35</b>, 2303621.<br/>[3] H. Roshan<i> et al.</i>, Near Infrared Light-Emitting Diodes Based on Colloidal InAs/ZnSe Core/Thick-Shell Quantum Dots. <i>Adv. Sci.</i> 2024, <b>11</b>, 2400734.