Reduction Expansion Synthesis as Strategy to Control Nitrogen Doping Level and Surface Area in Graphene
Graphene sheets doped with nitrogen were produced by the reduction-expansion (RES) method utilizing graphite oxide (GO) and urea as precursor materials. The simultaneous graphene generation and nitrogen insertion reactions are based on the fact that urea decomposes upon heating to release reducing g...
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MDPI AG
2015-10-01
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| Series: | Materials |
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| Online Access: | http://www.mdpi.com/1996-1944/8/10/5359 |
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| author | Russell Canty Edwin Gonzalez Caleb MacDonald Sebastian Osswald Hugo Zea Claudia C. Luhrs |
| author_facet | Russell Canty Edwin Gonzalez Caleb MacDonald Sebastian Osswald Hugo Zea Claudia C. Luhrs |
| author_sort | Russell Canty |
| collection | DOAJ |
| description | Graphene sheets doped with nitrogen were produced by the reduction-expansion (RES) method utilizing graphite oxide (GO) and urea as precursor materials. The simultaneous graphene generation and nitrogen insertion reactions are based on the fact that urea decomposes upon heating to release reducing gases. The volatile byproducts perform two primary functions: (i) promoting the reduction of the GO and (ii) providing the nitrogen to be inserted in situ as the graphene structure is created. Samples with diverse urea/GO mass ratios were treated at 800 °C in inert atmosphere to generate graphene with diverse microstructural characteristics and levels of nitrogen doping. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used to study the microstructural features of the products. The effects of doping on the samples structure and surface area were studied by X-ray diffraction (XRD), Raman Spectroscopy, and Brunauer Emmet Teller (BET). The GO and urea decomposition-reduction process as well as nitrogen-doped graphene stability were studied by thermogravimetric analysis (TGA) coupled with mass spectroscopy (MS) analysis of the evolved gases. Results show that the proposed method offers a high level of control over the amount of nitrogen inserted in the graphene and may be used alternatively to control its surface area. To demonstrate the practical relevance of these findings, as-produced samples were used as electrodes in supercapacitor and battery devices and compared with conventional, thermally exfoliated graphene. |
| first_indexed | 2024-04-11T22:59:17Z |
| format | Article |
| id | doaj.art-6190979742a64f60b8a8146341a4162e |
| institution | Directory Open Access Journal |
| issn | 1996-1944 |
| language | English |
| last_indexed | 2024-04-11T22:59:17Z |
| publishDate | 2015-10-01 |
| publisher | MDPI AG |
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| series | Materials |
| spelling | doaj.art-6190979742a64f60b8a8146341a4162e2022-12-22T03:58:15ZengMDPI AGMaterials1996-19442015-10-018107048705810.3390/ma8105359ma8105359Reduction Expansion Synthesis as Strategy to Control Nitrogen Doping Level and Surface Area in GrapheneRussell Canty0Edwin Gonzalez1Caleb MacDonald2Sebastian Osswald3Hugo Zea4Claudia C. Luhrs5Mechanical and Aerospace Engineering Department, Naval Postgraduate School, Monterey, CA 93943, USAMechanical and Aerospace Engineering Department, Naval Postgraduate School, Monterey, CA 93943, USAMechanical and Aerospace Engineering Department, Naval Postgraduate School, Monterey, CA 93943, USASchool of Materials Engineering, Purdue University, West Lafayette, IN 47907-2045, USADepartamento de Ingeniería Química y Ambiental, Universidad Nacional de Colombia, Bogotá, 111321, ColombiaMechanical and Aerospace Engineering Department, Naval Postgraduate School, Monterey, CA 93943, USAGraphene sheets doped with nitrogen were produced by the reduction-expansion (RES) method utilizing graphite oxide (GO) and urea as precursor materials. The simultaneous graphene generation and nitrogen insertion reactions are based on the fact that urea decomposes upon heating to release reducing gases. The volatile byproducts perform two primary functions: (i) promoting the reduction of the GO and (ii) providing the nitrogen to be inserted in situ as the graphene structure is created. Samples with diverse urea/GO mass ratios were treated at 800 °C in inert atmosphere to generate graphene with diverse microstructural characteristics and levels of nitrogen doping. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used to study the microstructural features of the products. The effects of doping on the samples structure and surface area were studied by X-ray diffraction (XRD), Raman Spectroscopy, and Brunauer Emmet Teller (BET). The GO and urea decomposition-reduction process as well as nitrogen-doped graphene stability were studied by thermogravimetric analysis (TGA) coupled with mass spectroscopy (MS) analysis of the evolved gases. Results show that the proposed method offers a high level of control over the amount of nitrogen inserted in the graphene and may be used alternatively to control its surface area. To demonstrate the practical relevance of these findings, as-produced samples were used as electrodes in supercapacitor and battery devices and compared with conventional, thermally exfoliated graphene.http://www.mdpi.com/1996-1944/8/10/5359reduction-expansion-synthesisnitrogen-doped graphene |
| spellingShingle | Russell Canty Edwin Gonzalez Caleb MacDonald Sebastian Osswald Hugo Zea Claudia C. Luhrs Reduction Expansion Synthesis as Strategy to Control Nitrogen Doping Level and Surface Area in Graphene Materials reduction-expansion-synthesis nitrogen-doped graphene |
| title | Reduction Expansion Synthesis as Strategy to Control Nitrogen Doping Level and Surface Area in Graphene |
| title_full | Reduction Expansion Synthesis as Strategy to Control Nitrogen Doping Level and Surface Area in Graphene |
| title_fullStr | Reduction Expansion Synthesis as Strategy to Control Nitrogen Doping Level and Surface Area in Graphene |
| title_full_unstemmed | Reduction Expansion Synthesis as Strategy to Control Nitrogen Doping Level and Surface Area in Graphene |
| title_short | Reduction Expansion Synthesis as Strategy to Control Nitrogen Doping Level and Surface Area in Graphene |
| title_sort | reduction expansion synthesis as strategy to control nitrogen doping level and surface area in graphene |
| topic | reduction-expansion-synthesis nitrogen-doped graphene |
| url | http://www.mdpi.com/1996-1944/8/10/5359 |
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