Defect Passivation and Förster-Type Energy Exchange in H2Pc-TMD Organic-Inorganic Heterostructures

Abstract

Organic - inorganic heterostructures (HS) combine the strong light absorption and exciton generation capabilities of organic molecules with the unique excitonic properties of layered transition metal dichalcogenides (TMDs), where the interfacial band alignment dictates the optical response. In this work, we investigate the influence of H2Pc molecules on CVD-grown MoS2 and WS2 monolayers using correlative microscopy techniques - Kelvin probe force microscopy (KPFM), photoluminescence (PL), and Raman spectroscopy. Comprehensive analysis of both electronic and optical properties provides detailed insights into the energy band alignment in these two HS. Despite their similar band alignments, the heterostructures exhibit strikingly different optical signatures. In the case of H2Pc/MoS2 HS, the effect of defect healing is more pronounced, while for the H2Pc/WS2 HS, strong indications of Förster energy transfer are observed. These findings highlight the critical role of transition dipole moment in addition to spectral overlap between donor emission and acceptor absorption in the design of optoelectronic devices.

References in corpus (8)

• Anomalous Lattice Vibrations of Single and Few-Layer MoS2
• Phonon and Raman scattering of two-dimensional transition metal dichalcogenides from monolayer, multilayer to bulk material
• Van der Waals heterostructures for high-performance device applications: challenges and opportunities
• Strong light-matter interactions between gap plasmons and two-dimensional excitons at ambient condition in a deterministic way
• Direct probing of phonon mode specific electron-phonon scatterings in two-dimensional semiconductor transition metal dichalcogenides: Symmetry and Berry phase
• Effects of CVD Growth Parameters on Global and Local Optical Properties of MoS${}_2$ Monolayers
• Impact of dark excitons on Förster type resonant energy transfer between dye molecules and atomically thin semiconductors
• Evidence of trion-libron coupling in chirally adsorbed single molecules