Enhanced Photocatalytic Activity of Anatase/Rutile Heterojunctions by Lanthanum and Tin Co-Doping
Anatase/rutile heterojunctions were prepared using the sol–gel method and modified by La/Sn single doping and co-doping. Sn doping promoted the transformation from anatase to rutile, while La doping inhibited the phase transformation. La and Sn co-doping showed an inhibitory effect. The co-doping of...
| Main Authors: | , , , , |
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| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2022-09-01
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| Series: | International Journal of Molecular Sciences |
| Subjects: | |
| Online Access: | https://www.mdpi.com/1422-0067/23/19/11339 |
| Summary: | Anatase/rutile heterojunctions were prepared using the sol–gel method and modified by La/Sn single doping and co-doping. Sn doping promoted the transformation from anatase to rutile, while La doping inhibited the phase transformation. La and Sn co-doping showed an inhibitory effect. The co-doping of La and Sn did not increase visible-light absorption, but exhibited a synergistic effect on inhibiting the recombination of photogenerated electrons and holes, which improved the photocatalytic activity on the basis of single-element modification. The first-order reaction rate constant of La/Sn co-doped sample was 0.027 min<sup>−1</sup>, which is 1.8 times higher than that of pure TiO<sub>2</sub> (0.015 min<sup>−1</sup>). Meanwhile, the mechanism of photodegradation of methylene blue (MB) by La/Sn co-doped anatase/rutile heterojunctions was discussed through electrochemical measurements and free-radical trapping experiments. |
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| ISSN: | 1661-6596 1422-0067 |