Metal-dependent interfacial properties in pthallocyanine-MoS₂ heterostructures

Mixed-dimensional heterostructures made by combining 2D materials with other systems of different dimensionality can exhibit unique interfacial effects and modify the properties of the individual constituent layers. Organic molecules are an attractive building block for these structures due to their synthetically tunable properties and ease of processing. Here we discuss interfacial charge transfer in metallophthalocyanine (MPc) – MoS₂ heterojunctions. These interfaces show heterojunction-specific optical absorption transitions, strong Raman enhancement, and defect emission quenching in the MoS₂, all of which depend the identity of the single metal (M) atom at the MPc core. Temperature dependent optical and electrical characterization were carried out to characterize and to understand the interfacial interactions. The metal core dependence provides a ‘knob’ for controlling opto-electronic properties of both the interface and the underlying layer, highlighting the complex and tunable nature of 0D/2D van Der Waals interfaces.