Large-scale production of graphene and reduced-graphene oxide (rGO) requires low-cost and ecofriendly synthesis methods. We employed a new, simple, cost-effective pyrolytic method to synthetize oxidized-graphenic nanoplatelets (OGNP) using bamboo pyroligneous acid (BPA) as source. Thorough analyses via high-resolution transmission electron microscopy and electron energy-loss spectroscopy provides a complete structural and chemical description at the local scale of these samples. In particular, we found that at the highest carbonization temperature the OGNP-BPA are mainly in sp 2 bonding configuration (sp 2 fraction of 87%). To determine the electrical properties of single nanoplatelets, these were contacted by Pt nanowires deposited through focused-ion-beam-induced deposition techniques.Increased conductivity by two orders of magnitude is observed as oxygen content decreases from 17 to 5%, reaching a value of 2.3x10 3 S/m at the lowest oxygen content. Temperature-dependent conductivity reveals a semiconductor transport behavior, described by the Mott three-dimensional variable range hopping mechanism. From the localization length, we estimate a band-gap value of 0.2(2) eV for an oxygen content of 5%. This investigation demonstrates the great potential of the OGNP-BPA for technological applications, given that their structural and electrical behavior is similar to the highlyreduced rGO sheets obtained by more sophisticated conventional synthesis methods.

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Graphite oxide is an interesting candidate for electronic applications; therefore, important efforts are dedicated to both large‐scaled and low‐cost graphite oxide production as an intermediate in graphene production. At the same time, research efforts are aimed at identifying the role of defects in the magneto‐electrical properties of platelets for electronic applications. In this paper, we present a new low‐cost fabrication process to obtain graphite oxide platelets of high crystal and thermoelectrical quality. The graphite oxide platelet samples were first obtained from bamboo pyroligneous acid (GO‐BPA) by thermal decomposition method using a pyrolysis system for different carbonization temperatures from 673 to 973 K. The GO‐BPA samples were characterized by using Raman, FTIR, XRD, and TEM techniques, whose results suggest that increased carbonization temperature increases graphite conversion, boundary defects, desorption of some organic compounds and phonon response, respectively. Finally, we discuss potential applications of the GO‐BPA samples involving phonon response that would benefit from a fully scaled technology, advanced electronic sensors, and devices.

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The oxidized derivative of graphene named Graphene oxide (GO) are attractive materials as optoelectronic devices due to their optical response in the mid-infrared wavelength spectral range; however, very large-scaled synthesis methods and optical characterization are required. Here, GO thin films are fabricated on quartz by implementing simple two-step pyrolysis processes by using renewable bamboo as source material. The effect of carbonization temperature (T CA) on the compositional, vibrational, and optoelectronic properties of the system are investigated. It was found that as T CA increases, graphite conversion rises, oxygen coverage reduces from 17 % to 4 %, and the band-gap energy monotonically decreases from 0.30 to 0.11 eV. Theoretical predictions of the energy band-gap variations with the oxide coverage obtained via density functional theory (DFT) computational simulations agree well with the experimental results, providing evidence of oxygen-mediated charge-transport scattering. Interestingly, in the optical response, increased T CA results in a blue-shift of the absorption and the absorbance spectrum can be correlated with the large size distribution of the graphitic nano-crystals of the samples. These results suggest that graphene oxide-bamboo pyroligneous acid (GO) thin films exhibit optoelectronic response useful in developing photodetectors and emitter devices in the mid-infrared (MIR) spectral range.