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Formation mechanism of zeolite-templated carbons
| Content Provider | Semantic Scholar |
|---|---|
| Author | Nishihara, Hirotomo Imai, Katsuaki Itoi, Hiroyuki Nomura, Keita Takai, Kazuyuki Kyotani, Takashi |
| Copyright Year | 2017 |
| Abstract | The formation mechanism of zeolite-templated carbons (ZTCs) is investigated. The carbon uptake into zeolite nanochannels during chemical vapor deposition (CVD) is found to proceed in the following three stages: (i) initial rapid carbon uptake from zeolite-particle surface to its center, (ii) gradual increase of carbon density at a constant rate, and (iii) termination of carbon deposition. The molecular-level structure evolution is also analyzed in detail. By CVD, curved nanographenes are formed inside the nanochannels of zeolite, and they are not perfectly connected each other. The subsequent heat treatment (>800 °C) coalesces the nanographenes to form a continuous 3D framework, and at the same time, a significant number of dangling bonds (non-terminated edge sites) are formed that are protected from air by the zeolite so that they are stable at room temperature. However on template removal, the dangling bonds react with ambient H2O or O2 and are terminated by oxygen-functional groups or H. The dangling bonds in the carbon/zeolite composite can also be terminated by H when the composite is subjected to a H2 treatment at 700 °C. In this case, the number of dangling bonds in the carbon/zeolite composite is decreased, and the addition of oxygen-functional groups when the template is removed becomes less significant. |
| Starting Page | 169 |
| Ending Page | 174 |
| Page Count | 6 |
| File Format | PDF HTM / HTML |
| DOI | 10.7209/tanso.2017.169 |
| Volume Number | 2017 |
| Alternate Webpage(s) | https://www.jstage.jst.go.jp/article/tanso/2017/280/2017_028002/_pdf/-char/en |
| Alternate Webpage(s) | https://doi.org/10.7209/tanso.2017.169 |
| Language | English |
| Access Restriction | Open |
| Content Type | Text |
| Resource Type | Article |
