Progress in research on nitrogen-doped nano-carbon materials at Ningbo Materials
Figure 1: Schematic diagram of the formation process of hollow carbon spheres Nitrogen-doped nano-carbon materials have become a major focus in the global carbon materials research field. This is largely due to the fact that nitrogen atoms possess one extra valence electron compared to carbon. When nitrogen is introduced into the hexagonal lattice of graphite, it can form structures such as pyridine, pyrrole, and graphitic nitrogen. These nitrogen-containing functional groups significantly enhance the surface reactivity and modify the electronic properties of nano-carbon materials. Among various nano-carbon structures, hollow carbon spheres stand out for their low density, high specific surface area, and unique cavity structures. These features make them highly promising for applications in drug delivery systems, nanoreactors, lithium-ion batteries, and enzyme immobilization. Traditionally, hollow carbon spheres are synthesized using methods like chemical vapor deposition, arc discharge, hydrothermal treatment, and template-based approaches. However, these techniques often face challenges such as poor size uniformity, thick walls, rough surfaces, and limited graphitization. To overcome these issues, researchers led by Dr. Zhang Jian from the Institute of New Energy Technology at the Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, collaborated with Hebei University of Science and Technology's School of Chemistry and Pharmaceutical Engineering. They developed an innovative approach using a template method to synthesize nitrogen-doped carbon nanospheres through the graphitization of ionic liquids. The new method involves using a nitrogen-rich ionic liquid as both a carbon and nitrogen source. It allows the formation of thin, uniform layers around monodisperse silica spheres, which are then removed after high-temperature graphitization (as shown in Figure 1). The resulting hollow carbon spheres exhibit excellent characteristics, including controllable size (up to 900 nm), ultra-thin walls (5–12 nm), mesoporous structure, and a nitrogen content of 3.2% (as shown in Figure 2). This breakthrough opens up new possibilities for the synthesis of nanostructured carbon materials and the study of functional group chemistry. Current efforts are focused on optimizing doping structures, exploring application performance, and investigating the feasibility of large-scale production. The findings were published in the Journal of Materials Chemistry A, volume 1, issue 1, in 2013 (DOI: 10.1039/C2TA01013E). This research not only advances the field of carbon materials but also highlights the potential of ionic liquids as versatile precursors for functional nanomaterials. SMT Splicing Tape Placement Box ShenZhen KDW Electronics Co.,Ltd , https://www.smtsplicetape.com
Figure 2 Characterization of hollow carbon spheres: (a) Scanning electron micrograph (b) Transmission electron micrograph (c) Infrared spectrum (d) N1s spectrum