g-C<sub>3</sub>N<sub>4</sub> quantum dots decorated spherical Bi<sub>2</sub>WO<sub>6</sub> photocatalyst and its enhanced photocatalytic activities mechanism
Three-dimensional(3D) Bi<sub>2</sub>WO<sub>6</sub> architecture was successfully synthesized <i>via</i> a hydr-othermal process. The g-C<sub>3</sub>N<sub>4</sub> quantum dots(QDs) were deposited on the surface of as-synthesized 3D Bi<sub...
| Main Authors: | , , , , , , , |
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| Format: | Article |
| Language: | zho |
| Published: |
Journal of Materials Engineering
2019-11-01
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| Series: | Cailiao gongcheng |
| Subjects: | |
| Online Access: | http://jme.biam.ac.cn/CN/Y2019/V47/I11/128 |
| Summary: | Three-dimensional(3D) Bi<sub>2</sub>WO<sub>6</sub> architecture was successfully synthesized <i>via</i> a hydr-othermal process. The g-C<sub>3</sub>N<sub>4</sub> quantum dots(QDs) were deposited on the surface of as-synthesized 3D Bi<sub>2</sub>WO<sub>6</sub> hierarchical structure to construct the novel Z-scheme g-C<sub>3</sub>N<sub>4</sub>/Bi<sub>2</sub>WO<sub>6</sub> heterojunctions <i>via</i> a simple impregnation-calcination method. The morphology, composition and visible-absorptive properties of as-synthesized samples were characterized by XRD, FE-SEM, TEM, UV-Vis-DRS techniques. Methylene blue(MB) and p-nitrophenol(p-NPh) were selected as model pollutant to investigate the effect of g-C<sub>3</sub>N<sub>4</sub> QDs on the photocataytic activity of Bi<sub>2</sub>WO<sub>6</sub> nanoarchitecture. The results reveal that as-prepared Bi<sub>2</sub>WO<sub>6</sub> exhibits the 3D architecture with the pore size of about 10nm <i>via</i> a simple impregnation-calcination method. g-C<sub>3</sub>N<sub>4</sub> QDs with the size of about 5nm can be deposited on the surface of secondary nanoplate of Bi<sub>2</sub>WO<sub>6</sub>. The photocatalytic activity of Z-scheme g-C<sub>3</sub>N<sub>4</sub>/Bi<sub>2</sub>WO<sub>6</sub> is superior to the pure g-C<sub>3</sub>N<sub>4</sub> and Bi<sub>2</sub>WO<sub>6</sub>, and 10%g-C<sub>3</sub>N<sub>4</sub>/Bi<sub>2</sub>WO<sub>6</sub> exhibits the best photocatalytic activity for MB and p-NPh. The apparent rate constant (<i>k</i><sub>app</sub>) for the degradation of MB is as high as 4.5 and 5.8 times, 2.6 and 1.6 times for p-NPh compared to that of pure g-C<sub>3</sub>N<sub>4</sub> and Bi<sub>2</sub>WO<sub>6</sub>, respectively. The O<sub>2</sub><sup>·-</sup> is the main reactive species during the photocatalytic process. The catalytic efficiency enhancement of g-C<sub>3</sub>N<sub>4</sub>/Bi<sub>2</sub>WO<sub>6</sub> relative to Bi<sub>2</sub>WO<sub>6</sub> or g-C<sub>3</sub>N<sub>4</sub> can be attributed to the formation of heterojunction between g-C<sub>3</sub>N<sub>4</sub> QDs and Bi<sub>2</sub>WO<sub>6</sub>, which suppresses the recombination of photogenerated electron/hole pairs as well as broaden the light absorption. |
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| ISSN: | 1001-4381 1001-4381 |