N掺杂石墨烯量子点修饰的N-TiO2/P掺杂多孔g-C3N4纳米管复合光催化剂用于降解抗生素和产氢

袁静舒; 张瑶; 张笑妍; 张俊杰; 张深根

doi:10.1007/s12613-023-2678-6

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文章导航 > 矿物冶金与材料学报（英文） > 2024 > 31(1): 165-178

Jingshu Yuan, Yao Zhang, Xiaoyan Zhang, Junjie Zhang, and Shen’gen Zhang, N-doped graphene quantum dot-decorated N-TiO₂/P-doped porous hollow g-C₃N₄ nanotube composite photocatalysts for antibiotic photodegradation and H₂ production, Int. J. Miner. Metall. Mater., 31(2024), No. 1, pp. 165-178. https://doi.org/10.1007/s12613-023-2678-6

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Jingshu Yuan, Yao Zhang, Xiaoyan Zhang, Junjie Zhang, and Shen’gen Zhang, N-doped graphene quantum dot-decorated N-TiO2/P-doped porous hollow g-C3N4 nanotube composite photocatalysts for antibiotic photodegradation and H2 production, Int. J. Miner. Metall. Mater., 31(2024), No. 1, pp. 165-178. https://doi.org/10.1007/s12613-023-2678-6

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研究论文

N掺杂石墨烯量子点修饰的N-TiO₂/P掺杂多孔g-C₃N₄纳米管复合光催化剂用于降解抗生素和产氢

1)
北京科技大学新材料技术研究院，北京 100083，中国
2)
西安翻译学院，西安 710105，中国
3)
北京科技大学顺德研究生院，佛山 528399，中国
4)
澳门科技大学月球与行星科学国家重点实验室，澳门特别行政区 820000，中国

通讯作者:
张深根 E-mail: zhangshengen@mater.ustb.edu.cn

文章亮点

(1) 合成了一种新型N-GQDs/N-TiO₂/P-g-C₃N₄多孔纳米管光催化剂。

(2) 实现了长波光源高效利用及光生电子定向转移。

(3) 阐明了N/P掺杂、Z型异质结、形貌调控及N-GQDs耦合的协同改性机制。

(4) 提出了0.1%G-TPCN的光催化反应机理及环丙沙星可能的5种降解路径。

中文摘要

仅响应紫外光(~3.2 eV)和光生电荷复合率高是纯TiO₂的两个主要缺点。本文联合N掺杂石墨烯量子点(N-GQDs)、形貌调控和异质结构筑合成了N-GQD/N掺杂TiO₂/P掺杂多孔中空g-C₃N₄纳米管(PCN)复合光催化剂(简称G-TPCN)。最佳样品(掺杂0.1wt% N-GQD的G-TPCN，记为0.1%G-TPCN)的光吸收性能显著增强，归因于P/N元素掺杂改变带隙、管状结构改善光捕集以及N-GQDs的上转换效应。此外，0.1%G-TPCN内部电荷分离和转移能力显著提高，其载流子浓度分别是N-TiO₂、PCN和N-TiO₂/PCN (TPCN-1)的3.7倍、2.3倍和1.9倍。这一结果归因于N-TiO₂与PCN之间形成的Z型异质结、N-GQDs优异的电子传导能力及多孔纳米管结构缩短电荷传输距离。与N-TiO₂、PCN和TPCN-1相比，0.1%G-TPCN在可见光下产H₂活性分别提高了12.4、2.3和1.4倍，环丙沙星(CIP)降解率分别提高了7.9、5.7和2.9倍。优化的性能得益于出色的光响应能力及提高的载流子分离和迁移效率。最后，提出了0.1%G-TPCN的光催化机理及CIP可能的五种降解途径。本研究阐明了多种改性策略协同提高0.1%G-TPCN光催化性能的机制，为合理设计新型光催化剂用于环境修复和太阳能转换提供了一种潜在方法。

关键词:

Research Article

N-doped graphene quantum dot-decorated N-TiO₂/P-doped porous hollow g-C₃N₄ nanotube composite photocatalysts for antibiotic photodegradation and H₂ production

+ Author Affiliations

1)
Institute for Advanced Materials and Technology, University of Science and Technology Beijing, Beijing 100083, China
2)
Xi’an Fanyi University, Xi’an 710105, China
3)
Shunde Graduate School of University of Science and Technology Beijing, Foshan 528399, China
4)
State Key Laboratory of Lunar and Planetary Sciences, Macau University of Science and Technology, Macau SAR 820000, China

The authors declare no conflicts of interest.
The online version contains supplementary material at https://doi.org/10.1007/s12613-023-2678-6.
* These authors contributed equally to this work

Corresponding author:
Shen’gen Zhang E-mail: zhangshengen@mater.ustb.edu.cn
Received: 18 February 2023; Revised: 15 May 2023; Accepted: 16 May 2023; Available online: 17 May 2023

Abstract

Abstract

Exclusive responsiveness to ultraviolet light (~3.2 eV) and high photogenerated charge recombination rate are the two primary drawbacks of pure TiO₂. We combined N-doped graphene quantum dots (N-GQDs), morphology regulation, and heterojunction construction strategies to synthesize N-GQD/N-doped TiO₂/P-doped porous hollow g-C₃N₄ nanotube (PCN) composite photocatalysts (denoted as G-TPCN). The optimal sample (G-TPCN doped with 0.1wt% N-GQD, denoted as 0.1%G-TPCN) exhibits significantly enhanced photoabsorption, which is attributed to the change in bandgap caused by elemental doping (P and N), the improved light-harvesting resulting from the tube structure, and the upconversion effect of N-GQDs. In addition, the internal charge separation and transfer capability of 0.1%G-TPCN are dramatically boosted, and its carrier concentration is 3.7, 2.3, and 1.9 times that of N-TiO₂, PCN, and N-TiO₂/PCN (TPCN-1), respectively. This phenomenon is attributed to the formation of Z-scheme heterojunction between N-TiO₂ and PCNs, the excellent electron conduction ability of N-GQDs, and the short transfer distance caused by the porous nanotube structure. Compared with those of N-TiO₂, PCNs, and TPCN-1, the H₂ production activity of 0.1%G-TPCN under visible light is enhanced by 12.4, 2.3, and 1.4 times, respectively, and its ciprofloxacin (CIP) degradation rate is increased by 7.9, 5.7, and 2.9 times, respectively. The optimized performance benefits from excellent photoresponsiveness and improved carrier separation and migration efficiencies. Finally, the photocatalytic mechanism of 0.1%G-TPCN and five possible degradation pathways of CIP are proposed. This study clarifies the mechanism of multiple modification strategies to synergistically improve the photocatalytic performance of 0.1%G-TPCN and provides a potential strategy for rationally designing novel photocatalysts for environmental remediation and solar energy conversion.
- N-doped TiO₂;
- N-doped graphene quantum dots;
- P-doped g-C₃N₄;
- porous hollow nanotube;
- heterojunction;
- photocatalysis

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