Construction of Type-II Heterojunctions in Crystalline Carbon Nitride for Efficient Photocatalytic H<sub>2</sub> Evolution
As an encouraging photocatalyst, crystalline carbon nitride (CCN) exhibits unsatisfactory photocatalytic activity and stability due to its rapid recombination of photo-generative carriers. Herein, high-crystalline g-C<sub>3</sub>N<sub>4</sub> was prepared, including CCN obtai...
| Main Authors: | , , , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2023-08-01
|
| Series: | Nanomaterials |
| Subjects: | |
| Online Access: | https://www.mdpi.com/2079-4991/13/16/2300 |
| _version_ | 1827728993300774912 |
|---|---|
| author | Jingyu Zhang Zhongliang Li Jialong Li Yalin He Haojie Tong Shuang Li Zhanli Chai Kun Lan |
| author_facet | Jingyu Zhang Zhongliang Li Jialong Li Yalin He Haojie Tong Shuang Li Zhanli Chai Kun Lan |
| author_sort | Jingyu Zhang |
| collection | DOAJ |
| description | As an encouraging photocatalyst, crystalline carbon nitride (CCN) exhibits unsatisfactory photocatalytic activity and stability due to its rapid recombination of photo-generative carriers. Herein, high-crystalline g-C<sub>3</sub>N<sub>4</sub> was prepared, including CCN obtained in KCl (K-CCN), LiCl-KCl mixture (Li/K-CCN), and LiCl-NaCl-KCl mixture (Li/Na/K-CCN), via the molten salt strategy using pre-prepared bulk carbon nitride (BCN) as a precursor. The obtained BCN sample was formed by heptazine-based units, which convert into triazine-based units for K-CCN. Heptazine and triazine are two isotypes that co-exist in the Li/K-CCN and Li/Na/K-CCN samples. Compared with BCN and other CCN samples, the as-prepared Li/Na/K-CCN sample exhibited the optimal photocatalytic hydrogen evolution rates (3.38 mmol·g<sup>−1</sup>·h<sup>−1</sup> under simulated sunlight and 2.25 mmol·g<sup>−1</sup>·h<sup>−1</sup> under visible light) and the highest apparent quantum yield (10.97%). The improved photocatalytic performance of the Li/Na/K-CCN sample is mainly attributed to the construction of type-II heterojunction and the institution of the built-in electric field between triazine-based CCN and heptazine-based BCN. This work provides a new strategy for the structural optimization and heterostructure construction of crystalline carbon nitride photocatalysts. |
| first_indexed | 2024-03-10T23:41:35Z |
| format | Article |
| id | doaj.art-8da456ededeb47ffa1a66d2e8037b039 |
| institution | Directory Open Access Journal |
| issn | 2079-4991 |
| language | English |
| last_indexed | 2024-03-10T23:41:35Z |
| publishDate | 2023-08-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Nanomaterials |
| spelling | doaj.art-8da456ededeb47ffa1a66d2e8037b0392023-11-19T02:26:59ZengMDPI AGNanomaterials2079-49912023-08-011316230010.3390/nano13162300Construction of Type-II Heterojunctions in Crystalline Carbon Nitride for Efficient Photocatalytic H<sub>2</sub> EvolutionJingyu Zhang0Zhongliang Li1Jialong Li2Yalin He3Haojie Tong4Shuang Li5Zhanli Chai6Kun Lan7Inner Mongolia Key Laboratory of Chemistry and Physics of Rare Earth Materials, College of Chemistry and Chemical Engineering, College of Energy Materials and Chemistry, Inner Mongolia University, Hohhot 010021, ChinaInner Mongolia Key Laboratory of Chemistry and Physics of Rare Earth Materials, College of Chemistry and Chemical Engineering, College of Energy Materials and Chemistry, Inner Mongolia University, Hohhot 010021, ChinaInner Mongolia Key Laboratory of Chemistry and Physics of Rare Earth Materials, College of Chemistry and Chemical Engineering, College of Energy Materials and Chemistry, Inner Mongolia University, Hohhot 010021, ChinaInner Mongolia Key Laboratory of Chemistry and Physics of Rare Earth Materials, College of Chemistry and Chemical Engineering, College of Energy Materials and Chemistry, Inner Mongolia University, Hohhot 010021, ChinaInner Mongolia Key Laboratory of Chemistry and Physics of Rare Earth Materials, College of Chemistry and Chemical Engineering, College of Energy Materials and Chemistry, Inner Mongolia University, Hohhot 010021, ChinaInner Mongolia Key Laboratory of Chemistry and Physics of Rare Earth Materials, College of Chemistry and Chemical Engineering, College of Energy Materials and Chemistry, Inner Mongolia University, Hohhot 010021, ChinaInner Mongolia Key Laboratory of Chemistry and Physics of Rare Earth Materials, College of Chemistry and Chemical Engineering, College of Energy Materials and Chemistry, Inner Mongolia University, Hohhot 010021, ChinaInner Mongolia Key Laboratory of Chemistry and Physics of Rare Earth Materials, College of Chemistry and Chemical Engineering, College of Energy Materials and Chemistry, Inner Mongolia University, Hohhot 010021, ChinaAs an encouraging photocatalyst, crystalline carbon nitride (CCN) exhibits unsatisfactory photocatalytic activity and stability due to its rapid recombination of photo-generative carriers. Herein, high-crystalline g-C<sub>3</sub>N<sub>4</sub> was prepared, including CCN obtained in KCl (K-CCN), LiCl-KCl mixture (Li/K-CCN), and LiCl-NaCl-KCl mixture (Li/Na/K-CCN), via the molten salt strategy using pre-prepared bulk carbon nitride (BCN) as a precursor. The obtained BCN sample was formed by heptazine-based units, which convert into triazine-based units for K-CCN. Heptazine and triazine are two isotypes that co-exist in the Li/K-CCN and Li/Na/K-CCN samples. Compared with BCN and other CCN samples, the as-prepared Li/Na/K-CCN sample exhibited the optimal photocatalytic hydrogen evolution rates (3.38 mmol·g<sup>−1</sup>·h<sup>−1</sup> under simulated sunlight and 2.25 mmol·g<sup>−1</sup>·h<sup>−1</sup> under visible light) and the highest apparent quantum yield (10.97%). The improved photocatalytic performance of the Li/Na/K-CCN sample is mainly attributed to the construction of type-II heterojunction and the institution of the built-in electric field between triazine-based CCN and heptazine-based BCN. This work provides a new strategy for the structural optimization and heterostructure construction of crystalline carbon nitride photocatalysts.https://www.mdpi.com/2079-4991/13/16/2300carbon nitrideheterojunctionbuild-in electric fieldphotocatalysis |
| spellingShingle | Jingyu Zhang Zhongliang Li Jialong Li Yalin He Haojie Tong Shuang Li Zhanli Chai Kun Lan Construction of Type-II Heterojunctions in Crystalline Carbon Nitride for Efficient Photocatalytic H<sub>2</sub> Evolution Nanomaterials carbon nitride heterojunction build-in electric field photocatalysis |
| title | Construction of Type-II Heterojunctions in Crystalline Carbon Nitride for Efficient Photocatalytic H<sub>2</sub> Evolution |
| title_full | Construction of Type-II Heterojunctions in Crystalline Carbon Nitride for Efficient Photocatalytic H<sub>2</sub> Evolution |
| title_fullStr | Construction of Type-II Heterojunctions in Crystalline Carbon Nitride for Efficient Photocatalytic H<sub>2</sub> Evolution |
| title_full_unstemmed | Construction of Type-II Heterojunctions in Crystalline Carbon Nitride for Efficient Photocatalytic H<sub>2</sub> Evolution |
| title_short | Construction of Type-II Heterojunctions in Crystalline Carbon Nitride for Efficient Photocatalytic H<sub>2</sub> Evolution |
| title_sort | construction of type ii heterojunctions in crystalline carbon nitride for efficient photocatalytic h sub 2 sub evolution |
| topic | carbon nitride heterojunction build-in electric field photocatalysis |
| url | https://www.mdpi.com/2079-4991/13/16/2300 |
| work_keys_str_mv | AT jingyuzhang constructionoftypeiiheterojunctionsincrystallinecarbonnitrideforefficientphotocatalytichsub2subevolution AT zhongliangli constructionoftypeiiheterojunctionsincrystallinecarbonnitrideforefficientphotocatalytichsub2subevolution AT jialongli constructionoftypeiiheterojunctionsincrystallinecarbonnitrideforefficientphotocatalytichsub2subevolution AT yalinhe constructionoftypeiiheterojunctionsincrystallinecarbonnitrideforefficientphotocatalytichsub2subevolution AT haojietong constructionoftypeiiheterojunctionsincrystallinecarbonnitrideforefficientphotocatalytichsub2subevolution AT shuangli constructionoftypeiiheterojunctionsincrystallinecarbonnitrideforefficientphotocatalytichsub2subevolution AT zhanlichai constructionoftypeiiheterojunctionsincrystallinecarbonnitrideforefficientphotocatalytichsub2subevolution AT kunlan constructionoftypeiiheterojunctionsincrystallinecarbonnitrideforefficientphotocatalytichsub2subevolution |