Direct chemical synthesis of nitrogen-doped graphynes with high supercapacitance via a cross-coupling copolymerization strategy

Development of graphyne-type carbon materials, which are constructed by different combination of sp(2) and sp hybridized carbon atoms, has been a thriving research hotspot in material science, due to their promising application in a range of energy and environmental fields. Herein, nitrogen-doped graphyne materials (NGY-1 and NGY-2) were directly synthesized by Sonogashira-Hagihara cross-coupling reaction, using hydrogen deficient multi-acetylene and polyhalide compounds as the comonomers. NGY-1 and NGY-2 possess twodimensional porous structure, high nitrogen content and homogenous nitrogen distribution. After heat treatment at the temperature of 800 ?, the obtained materials NGY-1-800 and NGY-2-800 demonstrate high supercapacitive energy storage performances with specific capacitances up to 312 F g(-1) at 0.1 A g(-1) and excellent cycling properties. Compared with NGY-1-800, NGY-2-800 obtained from the pyrazine-containing precursor, exhibits a better rate capability thanks to higher content of graphitic nitrogen doping. The copolymerization strategy developed here can potentially provide a rational design principle and open a new gateway for the construction of novel graphyne-type carbon materials for energy storage applications.

Automated summary

The development of graphyne-type carbon materials, constructed by sp(2) and sp hybridized carbon atoms, holds great promise for energy and environmental applications. In this study, nitrogen-doped graphyne materials were synthesized using a cross-coupling reaction and demonstrated high capacitance and cycling properties after heat treatment. The copolymerization strategy presented here provides a rational design principle for constructing novel graphyne-type carbon materials for energy storage.