Near to Long-Wave Infrared Mercury Chalcogenide Nanocrystals from Liquid Mercury

Nicolas Goubet (1, 2, 3) , Maxime Thomas (3) , Charlie Gréboval (2) , Audrey Chu (2) , Junling Qu (2) , Prachi Rastogi (2) , Sang-Soo Chee (2) , Mayank Goyal (2) , Yimin Zhang (2) , Xiang Zhen Xu (3) , Gregory Cabailh (4) , Sandrine Ithurria (3) , Emmanuel Lhuillier (2)

1 MONARIS - De la Molécule aux Nanos-objets : Réactivité, Interactions et Spectroscopies
2 INSP-E6 - Physico-chimie et dynamique des surfaces
3 LPEM - Laboratoire de Physique et d'Etude des Matériaux (UMR 8213)
4 INSP-E9 - Oxydes en basses dimensions

HgTe nanocrystals are currently the most promising colloidal material for infrared detection, combining broadly tunable infrared absorption and photoconductive properties. Current synthesis leads to a limited amount of material and relies on a highly toxic water-soluble form of Hg. Here, we explore the possibility of using Hg thiolate as Hg source and demonstrate that the latter can be formed in situ from liquid Hg. The developed protocol allows large masses (7 g) and highly concentrated (100 g/L) synthesis, which is a step forward for the transfer of this material towards industry. The transport properties of the material have also been investigated and we observe a transition from p to n-type with size. We observe that the threshold of the p to n switch depends on the growth method which enables for a given size of nanocrystal the formation of p-n junction. This work has great potential to design infrared sensor with optimized charge dissociation.

Mots clés: HgTe; nanocrystal; infarred; liquid mercury

Domaines: Matériaux

Nicolas Goubet, Maxime Thomas, Charlie Gréboval, Audrey Chu, Junling Qu, et al.. Near to Long-Wave Infrared Mercury Chalcogenide Nanocrystals from Liquid Mercury. Journal of Physical Chemistry C, 2020, ⟨10.1021/acs.jpcc.0c01255⟩. ⟨hal-02514168⟩