Incorporation of 2D black phosphorus (2D-bP) in P3HT/PMMA mixtures for novel materials with tuned spectroscopic, morphological and electric features

Abstract

Novel materials based on mixtures of immiscible polymers, namely poly (3-hexylthiophene-2,5-diyl) and poly (methyl methacrylate) (P3HT/PMMA), with dispersed phosphorene (2D-bP), obtained by liquid-phase exfoliation (LPE) of black phosphorus (bP) or by in situ polymerization technologies, were prepared for the first time. The new materials were characterized by Raman, UV–Vis, solid state 31P NMR spectroscopies, X-ray diffractometry (XRD), size exclusion chromatography (SEC), morphological (SEM), topographical (AFM) and thermal analysis (DSC and TGA) to investigate the physio-chemical features of both components, polymers and phosphorene owing the composites preparation. Good distribution of the nanoflakes, which preserve their structure and resulted intercalated and partially exfoliated, was achieved thanks to established interactions at the interface between the 2D-bP flakes and the polymers, especially with the P3HT phase, changing the morphology and topography of the mixtures. The preferential allocation of 2D-bP in P3HT, besides inducing a particular polymers phase segregation (a vertical phase separation with P3HT continuous phase onto the surface) encouraged testing these materials as an active layer in Organic Field Effect Transistor (OFET) devices. The data collected showed that the introduction of 2D-bP in P3HT/PMMA polymer mixtures is somewhat promising, giving an increase in mobility up to an order of magnitude with respect to the corresponding 2D-bP-free mixture.