Chalmpes Nikolaos, Asimakopoulos Georgios, Spyrou Konstantinos, Vasilopoulos Konstantinos C, Bourlinos Athanasios B, Moschovas Dimitrios, Avgeropoulos Apostolos, Karakassides Michael A, Gournis Dimitrios
Department of Materials Science & Engineering, University of Ioannina, 45110 Ioannina, Greece.
Physics Department, University of Ioannina, 45110 Ioannina, Greece.
Nanomaterials (Basel). 2020 Mar 20;10(3):566. doi: 10.3390/nano10030566.
Carbon formation from organic precursors is an energy-consuming process that often requires the heating of a precursor in an oven at elevated temperature. In this paper, we present a conceptually different synthesis pathway for functional carbon materials based on hypergolic mixtures, i.e., mixtures that spontaneously ignite at ambient conditions once its ingredients contact each other. The reactions involved in such mixtures are highly exothermic, giving-off sizeable amounts of energy; hence, no any external heat source is required for carbonization, thus making the whole process more energy-liberating than energy-consuming. The hypergolic mixtures described here contain a combustible organic solid, such as nitrile rubber or a hydrazide derivative, and fuming nitric acid (100% HNO) as a strong oxidizer. In the case of the nitrile rubber, carbon nanosheets are obtained, whereas in the case of the hydrazide derivative, photoluminescent carbon dots are formed. We also demonstrate that the energy released from these hypergolic reactions can serve as a heat source for the thermal conversion of certain triazine-based precursors into graphitic carbon nitride. Finally, certain aspects of the derived functional carbons in waste removal are also discussed.
由有机前驱体形成碳是一个耗能过程,通常需要在高温炉中加热前驱体。在本文中,我们提出了一种基于自燃混合物合成功能碳材料的概念上不同的合成途径,即一旦其成分相互接触就在环境条件下自燃的混合物。这种混合物中发生的反应是高度放热的,会释放出大量能量;因此,碳化过程不需要任何外部热源,从而使整个过程的能量释放大于能量消耗。这里描述的自燃混合物包含一种可燃有机固体,如丁腈橡胶或酰肼衍生物,以及作为强氧化剂的发烟硝酸(100% HNO)。对于丁腈橡胶,可得到碳纳米片,而对于酰肼衍生物,则形成光致发光碳点。我们还证明了这些自燃反应释放的能量可以作为热源,用于将某些基于三嗪的前驱体热转化为石墨氮化碳。最后,还讨论了衍生功能碳在废物去除方面的某些方面。