Sacrificial agent-free photocatalytic H2O2evolutionviatwo-electron oxygen reduction using a ternary α-Fe2O3/CQD@g-C3N4photocatalyst with broad-spectrum response
| Autor: | Wenwen Zhang, Hua Wang, Lixiang Zhang, Xi Chen, Luping Feng, Chunxian Zhang, Jie Jiang, Tingjiang Yan |
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| Rok vydání: | 2020 |
| Předmět: |
Materials science
Renewable Energy Sustainability and the Environment 02 engineering and technology General Chemistry 010402 general chemistry 021001 nanoscience & nanotechnology 01 natural sciences Exfoliation joint 0104 chemical sciences law.invention chemistry.chemical_compound Adsorption chemistry Chemical engineering law Electrode Photocatalysis General Materials Science Calcination Absorption (chemistry) 0210 nano-technology Ternary operation Melamine |
| Zdroj: | Journal of Materials Chemistry A. 8:18816-18825 |
| ISSN: | 2050-7496 2050-7488 |
| DOI: | 10.1039/d0ta05753c |
| Popis: | Ultrathin g-C3N4 nanosheets have been fabricated via a two-step calcination regulated by melamine precursors at a high heating rate (30 °C min−1). The resulting g-C3N4 nanosheets were further employed as carriers for the growth of carbon quantum dots (CQDs) and (110) exposed α-Fe2O3 through the PVP-enabled adsorption effects by a solvothermal process. It was discovered that the so fabricated ternary photocatalyst α-Fe2O3/CQD@g-C3N4 presented a broad-spectrum absorption range (up to 800 nm) and particularly enhanced active sites of photogenerated electrons for highly efficient photocatalytic oxygen reduction toward H2O2 evolution in pure water. A H2O2 production rate of 1.16 μM min−1 could be expected for the developed photocatalyst under visible light irradiation, which is about 19 times faster than that of pure ultrathin g-C3N4. Herein, the loaded Fe2O3 could transform the H2O2 evolution from two-step single-electron reduction into one-step two-electron one, as verified by the various active species experiments and rotating ring-disk electrode tests. This work presents a new perspective in designing ultrathin g-C3N4 through a simple method of precursor-regulated calcination, which features more outstanding advantages than the conventional exfoliation of bulk g-C3N4 towards ultrathin g-C3N4. More importantly, it provides an optimized photocatalytic reaction route of two-electron oxygen reduction for efficient H2O2 production in pure water under visible light irradiation, without the need for noble metals or organic sacrificial agents. |
| Databáze: | OpenAIRE |
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