Quasiparticle electronic structure of phthalocyanine:TMD interfaces from first-principles GW

Interfaces formed between monolayer transition metal dichalcogenides and (metallo)phthalocyanine molecules are promising in energy applications and provide a platform for studying mixed-dimensional molecule-semiconductor heterostructures in general. An accurate characterization of the frontier energy level alignment at these interfaces is key in the fundamental understanding of the charge transfer dynamics between the two photon absorbers. Here, we employ the first-principles substrate screening GW approach to quantitatively characterize the quasiparticle electronic structure of a series of interfaces: metal-free phthalocyanine (H₂Pc) adsorbed on monolayer MX₂ (M = Mo, W; X = S, Se) and zinc phthalocyanine (ZnPc) adsorbed on MoX₂ (X = S, Se). Furthermore, we reveal the dielectric screening effect of the commonly used α-quartz (SiO₂) substrate on the H₂Pc:MoS₂ interface using the dielectric embedding GW approach. Our calculations furnish a systematic set of GW results for these interfaces, providing the structure-property relationship across a series of similar systems and benchmarks for future experimental and theoretical studies.