共 50 条
Site-exposed Ti3C2 MXene anchored in N-defect g-C3N4 heterostructure nanosheets for efficient photocatalytic N2 fixation
被引:47
|作者:
Sun, Cong
[1
]
Chen, Zhiqiang
[1
]
Cui, Jian
[1
]
Li, Kang
[1
]
Qu, Hongxia
[1
]
Xie, Huifang
[1
]
Zhong, Qin
[1
]
机构:
[1] Nanjing Univ Sci & Technol, Sch Chem Engn, Nanjing 210094, Jiangsu, Peoples R China
基金:
中国国家自然科学基金;
关键词:
GRAPHITIC CARBON NITRIDE;
OXYGEN VACANCIES;
NITROGEN-FIXATION;
AMMONIA-SYNTHESIS;
METAL CARBIDES;
DINITROGEN;
REDUCTION;
WATER;
HETEROJUNCTION;
CONVERSION;
D O I:
10.1039/d0cy01955k
中图分类号:
O64 [物理化学(理论化学)、化学物理学];
学科分类号:
070304 ;
081704 ;
摘要:
Exploring highly active centers for N ;N triple-bond activation and the suppression of the competing H-2 evolution reaction (HER) are key considerations for photocatalytic N-2 fixation. As a novel 2D transition-metal carbide, Ti3C2 nanosheets (MXenes) have been recently considered as a promising N-2 reduction reaction (NRR) active center. However, little of the expected progress in the use of Ti3C2 for photocatalytic N-2 fixation has been achieved. Herein, we report a novel 2D/2D Ti3C2/N-defect g-C3N4 heterostructure photocatalyst exhibiting highly enhanced photocatalytic nitrogen fixation activity, with an NH3 yield of 5.792 mg h(-1) g(-1). This study demonstrates that the heterostructure was constructed by filling the oxygen-terminals of Ti3C2 in the N-defects of g-C3N4 to form C-O-Ti interactions. Together, the construction of the hetero-interface and the introduction of N-defects contribute to rapid interfacial charge transfer to the active sites. Importantly, the exposed edge Ti of Ti3C2 was confirmed to be the active site for N-2 adsorption and activation, and these active Ti sites exhibit desirable NRR selectivity via suppressing the competing HER. Finally, a mechanism for photocatalytic N-2 fixation was proposed to reveal the evolution of the redox circle that originated from the multi-valence Ti species during the N-2 adsorption, activation, and dissociation process.
引用
收藏
页码:1027 / 1038
页数:12
相关论文