▎ 摘　　要

Structurally well-defined graphene tianoribbons (GNRs) have attracted great interest as next generation semiconductor materials. The functionalization of GNRs with polymeric side chains, which can widely broaden GNR-related studies on physiochemical properties and potential applications, has remained unexplored. Here,;we demonstrate the bottom-tip solution synthesis of defect-free GNRs grafted with flexible poly(ethylene oxide) (PEO) chains. The GNR backbones possess an armchair edge structure with a width of 1.0-1.7 nm and mean lengths of 15-60 nm, enabling near-infrared absorption and a low bandgap of 1.3 eV. Remarkably, the PEO grafting renders the GNRs superb dispersibility in common organic solvents, with a record concentration of similar to 1 mg mI,(-1)(for GNR backbone) that is much higher than that (<0.01 mg mL(-1)) of reported GNRs. Moreover, the PEO-ftinctionalized GNRs can be readily dispersed in Water, accompanying with supramolecular helical nanowire formation. Scanning probe microscopy reveals raft -like self -assembled monolayers of uniform GNRs on graphite substrates. Thin-film-based field-effect transistors (FETs) of the GNRs exhibit a high carrier mobility of similar to 0.3 cm(2) V-1 s(-1), manifesting promising application of the polymerfunctionalized GNRs in electronic devices.