Shape-Dependent Carrier Dynamics in Chemical Vapor Deposition-Grown CsPbBr ₃ Clusters on Oxide and Two-Dimensional Semiconductors

We investigate morphology-dependent photoluminescence (PL) and carrier dynamics of chemical vapor deposition-grown CsPbBr 3 microclusters formed as discrete cubic, spherical, and tetrahedral crystals on silicon dioxide (SiO 2 )/silicon and on monolayer molybdenum disulfide (MoS 2 ).The MoS 2 underlayer enables a direct comparison between an inert SiO 2 surface and a monolayer MoS 2 within a single specimen.Shape-resolved PL and time-resolved PL reveal i) modest blue-shifts for tetrahedra relative to cubes and ii) systematically shorter lifetimes on MoS 2 than on SiO 2 , consistent with type-II band alignment and interlayer charge transfer.A shape-dependent lifetime ordering emerges (tetrahedron < cube < sphere), which we attribute to facet-related defect densities and effective contact area at the CsPbBr 3 /MoS 2 interface.