Ambipolar charge transport in an organic/inorganic van der Waals p–n heterojunction

Abstract

Hybrid two-dimensional (2D) van der Waals (vdW) p–n junctions are attractive due to the controlled synthesis of the physical performances of organic semiconductors and quantum confinement effects of 2D materials, enabling highly tunable optoelectronic performances as well as low-cost processability. Here, hybrid 2D heterostructures are fabricated using a p-type semiconducting polymer (PDVT-10) and n-type MoS₂. An ultra-thin film (∼9 nm) of the PDVT-10 polymer is formed using the Langmuir–Schaefer (LS) technique. Large-scale MoS₂ monolayers are prepared using a chemical vapor deposition (CVD) method. The PDVT-10/MoS₂ vertical heterojunction devices show ambipolar charge transport properties with a p-type maximum field-effect mobility of 0.3 cm² V⁻¹ s⁻¹ and an n-type maximum field-effect mobility of 2.45 cm² V⁻¹ s⁻¹. In addition, the heterojunctions exhibit a great photoresponse under white light as well as a clear rectifying behavior.