Atomic-scale construction and characterization of quantum dots array and poly-fluorene chains via 2,7-dibromofluorene on Au(1 1 1)

On-Surface Synthesis of a Carbon Nanoribbon Composed of 4–5–6–8-Membered Rings

“…Subsequent thermal annealing of the sample at 490 K for about 30 min induces dehalogenative aryl–aryl coupling reactions, resulting in the formation of one-dimensional polymers, i.e., polyfluorene chains (Figure a). Further close-up STM (Figure b) and nc-AFM (Figure c) images reveal the formation of individual polyfluorene chain, similar to the previously reported one, whose periodicity along the chain arising from protrusions is 8.7 ± 0.2 Å (Figure S2a). The proposed model of such a polymer chain is overlaid on the STM image.…”

“…As shown in the nc-AFM image (Figure c), the brighter contrasts at the sites of −CH 2 – groups in the polyfluorene chain are similar to those in the monomers, indicating that the −CH 2 – groups are still intact at 490 K. In addition, most −CH 2 – groups in Figure c are oriented on the same side of the polyfluorene chain, which originates from the sufficient length of such flexible polymer chains, providing the proper geometry for further lateral fusion. However, other random orientations of −CH 2 – groups along the polyfluorene chains are also observed (Figure S2b), like those reported in literatures. , Further, differential conductance spectroscopy (d I /d V ) measurements were performed to characterize the electronic structure of the single polyfluorene chain. The d I /d V spectra shown in Figure d suggest a considerably large bandgap of 4.4 eV.…”

“…As shown in Figure S6, we also tried another precursor (2-bromo-7-iodo-9 H -fluorene) and found that the polyfluorene chains are normally shorter than the ones formed by DIF precursor, and more importantly, no lateral fusion reaction occurred at the same experimental conditions as above. Also, no lateral fusion reaction was reported with another similar precursor (2,7-dibromo-9 H -fluorene) in literature …”

“…However, other random orientations of −CH 2 − groups along the polyfluorene chains are also observed (Figure S2b), like those reported in literatures. 35,42 Further, differential conductance spectroscopy (dI/dV) measurements were performed to characterize the electronic structure of the single polyfluorene chain. The dI/ dV spectra shown in Figure 2d suggest a considerably large bandgap of 4.4 eV.…”

Fluorene intercalated graphene oxide based CoQ10 imprinted polymer composite as a selective platform for electrochemical sensing of CoQ10

“…Fluorene and its derivative have been explored extensively for their applications in the fabrication of blue polymer, OLED, OSC, etc. 25 There are several reports about the homo- and co-polymers of fluorene that show excellent conductivity and electrochromic properties. 26 Therefore, fluorene was intercalated into the sheets of GO as functional monomer to facilitate the pre-polymerization complexation between Fl Int.…”