Nitrogen-doped porous microsphere carbons derived from glucose and aminourea for high-performance supercapacitors

Abstract

Nitrogen-doped porous microsphere carbons were prepared from glucose and aminourea through hydrothermal carbonization (HTC) followed by KOH activation. Aminourea used as nitrogen precursor contributes to the introduction of appropriate nitrogen content and well-developed porosity during KOH activation. The prepared samples exhibit particular nanostructure with high specific surface area and appropriate pore size distribution, which provides short ion diffusion channels and low-resistant pathways for the penetration and transportation of electrolyte. In addition, the doped-nitrogen atoms can give rise to the pseudo-capacitive behavior for as-prepared samples. Those special characteristics endow the final product with high specific surface area (2594 m2 g−1), high specific capacity (390 F g−1 at 0.5 A g−1), high rate capability (260 F g−1 at 20 A g−1), and long life span (90% retention over 10000 cycles). Therefore, nitrogen-doped porous microsphere carbons with excellent electrochemical performance show great potential in the field of electrochemical energy storage.