Thermal reduction of graphite oxide in the presence of nitrogen-containing dyes

Abstract

Thermal reduction of graphite oxide (GO) is considered as a prospective method for the preparation of high-performance graphene-based materials. However, this method has certain limitations, and the major is that this exothermic process is difficult to control. In this research, we focused on the kinetic studies of the reduction of graphite oxide using non-isothermal differential calorimetry (DSC) method. Six GO nanocomposites with dyes were tested to study the shift in kinetic parameters. The apparent reaction order is determined to be ca 0.7 for the thermal decomposition of pure GO, while in the presence of dye molecules it increases sometimes reaching a value of 2.0 for higher dye concentrations. Decisively, the thermal decomposition of pure GO can be presented as an intermediate between a zero- and first-order reaction, while the introduction of dye molecules turns a certain part of the energy consumption via the bimolecular pathway. Our research revealed that the process of GO thermal decomposition can be operated and properties of the final product (reduced graphene oxide (rGO) and its derivatives) can be adjusted more precisely using additive molecules, which interact with GO sheets.

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Acknowledgements

We acknowledge the financial support from the Lithuanian Research Council via measure “Towards Future Technologies” (Project No. LAT 11/2016).

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Barkauskas, J., Gaidukevič, J. & Niaura, G. Thermal reduction of graphite oxide in the presence of nitrogen-containing dyes. Carbon Lett. (2021). https://doi.org/10.1007/s42823-021-00228-3

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Keywords

  • Graphite oxide
  • Nanocomposites
  • Thermal reduction
  • Reaction mechanism
  • Reaction order