π‐Conjugated Molecules Crosslinked Graphene‐Based Ultrathin Films and Their Tunable Performances in Organic Nanoelectronics

Abstract

Graphene‐based ultrathin films with tunable performances, controlled thickness, and high stability are crucial for their uses. The currently existing protocols, however, could hardly simultaneously meet these requirements. Using amino‐substituted π‐conjugated compounds, including 1,4‐diaminobenzene (DABNH2), benzidine (BZDNH2), and 5,10,15,20‐tetrakis (4‐aminophenyl)‐21H,23H‐porphine (TPPNH2), as cross‐linkages, a new protocol through which graphene oxide (GO) nanosheets can be anchored on solid supports with a high stability and controlled thickness via a layer‐by‐layer method is presented. A thermal annealing leads to the reduction of the films, and the qualities of the samples can be inherited by the as‐produced reduced GO films (RGO). When RGO films are integrated as source/drain electrodes in OFETs, tunable performances can be realized. The devices based on the BZDNH2‐crosslinked RGO electrodes exhibit similar electrical behaviors as those based on the non‐π‐conjugated compound crosslinked electrodes, while improved performances can be gained when those crosslinked by DABNH2 are used. The performances can be further improved when RGO films crosslinked by TPPNH2 are employed. This work likely paves a new avenue for graphene‐based films of tunable performances, controlled thickness, and high stability.

Reduced Graphene Oxide@Mesoporous Silica–Doxorubicin/Hydroxyapatite Inorganic Nanocomposites: Preparation and pH–Light Dual‐Triggered Synergistic Chemo‐Photothermal Therapy

“…The Raman spectra of GO, rGO@mSiO 2 , and rGO@mSiO 2 /HA are shown in Figure b. Two typical intense peaks of GO at ν̃ ≈ 1354 (D band) and 1599 cm –1 (G band) correspond to the stretching modes of sp 2 ‐ and sp 3 ‐hybridized carbon atoms, respectively . The intensity ratio of the D band to the G band ( I D / I G ) changes from 0.894 to 0.914 in rGO@mSiO 2 , and this change corroborates the partial reduction of GO upon high‐temperature treatment and combination with SiO 2 .…”

Ultrasensitive and stable all graphene field‐effect transistor‐based Hg2+ sensor constructed by using different covalently bonded RGO films assembled by different conjugate linking molecules

“…The GO‐related groups are also clearly observable. These experimental data indicate that TAPP and GO were successfully integrated in the (APTMS/GO)/(TAPP/GO) N films via the covalent LBL method 34 . The Raman spectra of the two formulated GO films are displayed in Figure 1B .…”

“…However, as displayed in Figure 1E, the resulting electric conduction performance of (APTMS/RGO)/(TAPP/RGO) N was outstanding owing to different layer charge transport functions of two coupling agents. (ii) The contact resistances between the electrodes and semiconductor layers of AG‐FET and Au/RGO/Au FET were measured via the transfer length method (TLM) 34,42 . As shown in Figure 2F, the contact resistance between electrodes and semiconductor in AG‐FET is 4.5 × 10 3 Ω·cm much smaller than the contact resistance of 9.5 × 10 4 Ω·cm between electrodes and semiconductor in Au/RGO/Au FET.…”

Pristine graphdiyne-hybridized photocatalysts using graphene oxide as a dual-functional coupling reagent

“…1625 cm À1 , could be observed distinctly. 27,33,34 In the cases of the GO/GD, the CQO carbonyl stretching band of GO at 1731 cm À1 could still be observed evidently, while the peak representing the skeletal vibrations of the aromatic rings of GD at 1587 cm À1 could not be discerned, since it is covered up by the broad band of the vibrations of the adsorbed water molecules of GO. Significantly, in the cases of the Ag/AgBr/GO and Ag/AgBr/GO/ GD species, the CQO carbonyl stretching band shifts to a lower wavenumber of ca.…”