Ligand—driven optoelectronic tuning in Mn2 + —doped CsPbCl3 nanocrystals: Constructing efficient heterojunctions for flexible NIR application

The development of efficient and stable near—infrared (NIR) emitters using solution—processable materials remains a key challenge for flexible optoelectronics. This study addresses this need by constructing a novel ternary heterostructure through a room—temperature, sulfur—anion mediated transformation of CsPbCl 3 : Mn 2+ nanocrystals. Unlike conventional binary systems, this architecture enables a unidirectional energy cascade: from the CsPbCl 3 host to Mn 2+ emitters, and subsequently to the in—situ formed PbS domain, resulting in enhanced NIR emission. Systematic investigation reveals that optimal incorporation of C 6 H 18 SSi 2 is critical for modulating the heterointerface, which in turn opens a highly efficient energy transfer pathway. The resulting nanocomposite exhibits exceptional stability, retaining 95 % of its photoluminescence after six months under ambient conditions. Furthermore, the successful fabrication of flexible films with uniform electroluminescence underscores the practical potential of this heterostructure for next—generation optoelectronic devices.