Comparison study of structural and optical properties of boron-doped and undoped graphene oxide films

We prepared boron (B)-doped graphene oxides (G0s) by means of annealing the films, which were obtained from the suspensions of GO and H3BO3 in N,N-Dimethylformamide solvent. The interplanar spacing of as-synthesized GO in X-ray diffraction spectra has been reduced by the thermal annealing at 1100 degrees C. First-order Raman spectra revealed that the intensity ratio of the D and G bands of B-doped GO was significantly lower than those of as-synthesized and annealed GOs, suggesting more graphitization of the B-doped GO due to doping effect. The C1s X-ray photoelectron spectroscopy (XPS) of B-doped GO films not only indicated that considerable amount of functional groups has been removed but also exhibited the peak of C-B band at around 283.7 eV. Additionally, the B1s XPS spectrum of B-doped GOs could be deconvoluted into several peaks centered at 187.2, 188.9, 190.3, 192.0 and 193.7 eV, being attributed to the presence of B atom in B4C, B-sub-C, BC2O, BCO2 and B2O3, respectively. Comparison of the photoluminescence spectra of B-doped GO with that of 1100 degrees C-annealed GO indicated that the overall intensity was decreased, presumably due to the B-induced graphitization. An additional band at around 600-700 nm from B-doped GO is attributed to the generated boron carbide phases. (C) 2012 Elsevier B.V. All rights reserved.