Semiconducting Spaghetti-like Organic–Inorganic Nanojunctions via Sequential Self-Assembly of Conjugated Polymers and Quantum Dots

Abstract

The ability to direct semiconducting polymers and inorganic nanomaterials into complex assemblies renders the creation of organic–inorganic nanocomposites with unique properties and functionalities. Herein, we report the crafting of highly interconnected semiconducting organic–inorganic nanocomposites (referred to as nanojunctions) comprising long poly(3-hexylthiophene) (P3HT) nanowires and lead telluride (PbTe) quantum dots (QDs) via two successive self-assembly processes. First, P3HT chains self-assemble into ultralong one-dimensional (1D) nanowires owing to interchain π–π stacking, followed by self-assembly of PbTe QDs on both sides of the P3HT nanowires driven by attractive van der Waals interactions between the hexyl side chains of P3HT and aliphatic chains capped on the surface of PbTe QDs. Notably, an integrated experimental and Monte Carlo (MC) simulation study reveals that the surface coverage of PbTe QDs within the P3HT/PbTe nanojunctions as well as the distance between adjacent PbTe QDs could be conveniently tailored via tuning the QD concentration. Interestingly, the photoluminescence of P3HT progressively decreases with an increased loading of PbTe QDs because of effective charge transfer from P3HT to PbTe. Conceptually, this two-step self-assembly strategy can be readily extended to other semiconducting polymers and a diversity of nanomaterials for potential applications in optoelectronic materials and devices.