| Autor: |
David James, Martin, Kaipei, Qiu, Stephen Andrew, Shevlin, Albertus Denny, Handoko, Xiaowei, Chen, Zhengxiao, Guo, Junwang, Tang |
| Rok vydání: |
2014 |
| Předmět: |
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| Zdroj: |
Angewandte Chemie (International Ed. in English) |
| ISSN: |
1521-3773 |
| Popis: |
The major challenge of photocatalytic water splitting, the prototypical reaction for the direct production of hydrogen by using solar energy, is to develop low-cost yet highly efficient and stable semiconductor photocatalysts. Herein, an effective strategy for synthesizing extremely active graphitic carbon nitride (g-C3N4) from a low-cost precursor, urea, is reported. The g-C3N4 exhibits an extraordinary hydrogen-evolution rate (ca. 20,000 μmol h(-1) g(-1) under full arc), which leads to a high turnover number (TON) of over 641 after 6 h. The reaction proceeds for more than 30 h without activity loss and results in an internal quantum yield of 26.5% under visible light, which is nearly an order of magnitude higher than that observed for any other existing g-C3N4 photocatalysts. Furthermore, it was found by experimental analysis and DFT calculations that as the degree of polymerization increases and the proton concentration decreases, the hydrogen-evolution rate is significantly enhanced. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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