温度和pH值对水溶液中氧化石墨烯还原特性的影响.docVIP

  Temperature and pH effect on reduction of graphene oxides in aqueous solution# 5 10 15 20 25 30 35 40 45 Tai Guoan1, Zeng Tian2* (1. The State Key Laboratory of Mechanics and Control of Mechanical Structures, College of Aerospace Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China; 2. College of Material Science and Technology, Nanjing University of Aeronautics and Astronautics, 29 Yudao Street, Nanjing 210016. China) Abstract: In this paper, the reduced graphene oxides (RGOs) were usually obtained by hydrazine reduction, but hydrazine-related compounds are corrosive, highly flammable and very hazardous, and the obtained RGOs heavily aggregate. Here we extensively investigated the effect of temperature and pH value on the structure of RGOs in hydrothermal environments without any reducing agents. The attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectra showed that reduction rate of GOs remarkably increased with the temperature from 100 to 180℃ and with pH value from 3 to 10. It was found that the large-scale RGOs were cut into small nanosheets with size from several to few tens of nanometers with increasing temperature and duration. This study provides a feasible approach to controllably reduce GO with different nanostructures such porous structures and quantum dots for applications in optoelectronics and biomedicals Key words: hydrothermal synthesis; reduced graphene oxide; deoxygenation 0 Introduction Graphene, a single layer of hexagonally arranged carbon atoms, has attracted tremendous interests owing to its remarkable properties such as extremely high mobilities, fascinating thermal and mechanical properties [1-3], which make it an attractive candidate for potential applications such as field emitters, flexible electronic circuitry, supercapacitors and nanocomposites [4-7]. To date, graphene has been prepared by various techniques, such as mechanical cleavage of graphite, chemical vapor deposition,