Nitrogen-enriched ordered mesoporous carbons through direct pyrolysis in ammonia with enhanced capacitive performance

Journal Article · Thu May 02 00:00:00 EDT 2013 · Journal of Materials Chemistry. A

DOI:https://doi.org/10.1039/c3ta11342f· OSTI ID:1097511

Wang, Xiqing ^[1]; Liu, Chen-Guang ^[2]; Neff, David ^[2]; Fulvio, Pasquale F. ^[3]; Mayes, Richard T. ^[3]; Zhamu, Aruna ^[4]; Fang, Qing ^[2]; Chen, Guorong ^[2]; Meyer, Harry M. ^[5]; Jang, Bor Z. ^[2]; Dai, Sheng ^[6]

---

1. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Chemical Sciences Division; Nanotek Instruments Inc., Dayton, OH (United States)
2. Nanotek Instruments Inc., Dayton, OH (United States)
3. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Chemical Sciences Division
4. Angstron Materials Inc., Dayton, OH (United States)
5. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Materials Science & Technology Division
6. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Chemical Sciences Division; Univ. of Tennessee, Knoxville, TN (United States). Dept. of Chemistry

Self-assembly of phenolic resins and a Pluronic block copolymer via the soft-template method enables the formation of well-organized polymeric mesostructures, providing an easy way for preparation of ordered mesoporous carbons (OMCs). However, direct synthesis of OMCs with high nitrogen content remains a significant challenge due to the limited availability of nitrogen precursors capable of co-polymerizing with phenolic resins without deterioration of the order of mesostructural arrangement and significant diminishment of nitrogen content during carbonization. In this work, we demonstrate pyrolysis of the soft-templated polymeric composites in ammonia as a direct, facile way towards nitrogen-enriched OMCs (N-OMCs). We find thisapproach does not require any nitrogen-containing carbon precursors or post-treatment, but takes advantage of the preferential reaction and/or replacement of oxygen with nitrogen species, generated by decomposition of ammonia at elevated temperatures, in oxygen-rich polymers during pyrolysis. It combines carbonization, nitrogen functionalization, and activation into one simple process, generating N-OMCs with a uniform pore size, large surface area (up to 1400 m² g^-1), and high nitrogen content (up to 9.3 at%). More importantly, the ordering of the meso-structure is well-maintained as long as the heating temperature does not exceed 800 °C, above which (e.g., 850 °C) a slight structural degradation is observed. In conclusion, when being used as electrode materials for symmetric electric double layer capacitors, N-OMCs demonstrate enhanced capacitance (6.8 μF cm^₋2vs. 3.2 μF cm^₋2) and reduced ion diffusion resistance compared to the non-NH₃-treated sample.

• Research Organization: Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
• Sponsoring Organization: USDOE Office of Science (SC)
• DOE Contract Number: AC05-00OR22725
• OSTI ID: 1097511
• Journal Information: Journal of Materials Chemistry. A, Vol. 1, Issue 27; ISSN 2050-7488
• Publisher: Royal Society of Chemistry
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE