Synthesis of ultrathin two-dimensional organic–inorganic hybrid perovskite nanosheets for polymer field-effect transistors

Abstract

In this study, free-standing phenylethylammonium lead halide perovskite (i.e. (PEA)₂PbX₄ (PEA = C₈H₉NH₃, X = Cl, Br, and I)) nanosheets (NSs) with few-layer thickness were synthesized using a facile antisolvent method. The as-prepared (PEA)₂PbX₄ NSs could be well-dispersed in organic solvents such as toluene and hexane. By incorporating the (PEA)₂PbX₄ NSs into poly(3-hexylthiophene) (P3HT) in toluene, (PEA)₂PbX₄ NSs: P3HT composite films were fabricated as channel layers for field-effect transistors (FETs) through spin coating. All of the resultant FETs show promising hole transport and current saturation behaviour at room temperature. Notably, the FET based on (PEA)₂PbI₄ NSs: P3HT exhibited the best hole mobility, μ_h, of 1.43 × 10⁻¹ cm² V⁻¹ s⁻¹ and threshold voltage, V_th, of 5.19 V. These results pave a new way for the application of 2D organic–inorganic hybrid perovskite NSs as channel materials in high-performance FETs.