Highly active Cs2SnCl6/C3N4 heterojunction photocatalysts operating via interfacial charge transfer mechanism
Highly active Cs2SnCl6/C3N4 heterojunction photocatalysts operating via interfacial charge transfer mechanism
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通过界面电荷转移机制运行的高活性 Cs2SnCl6/C3N4 异质结光催化剂
DOI：
10.1016/j.jhazmat.2022.129694
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发表时间：
2022
影响因子：
13.6
通讯作者：
Fan Dong
中科院分区：
文献类型：
--
作者：
Tianqi Tan;Xuemei Wang;Xi Zhou;Hao Ma;Ruimei Fang;Qin Geng;Fan Dong
本研究构建了一种新型的无铅钙钛矿异质结Cs2 SnCl 6 /C3 N4复合材料，并将其应用于光催化净化NO。优化设计后的Cs2 SnCl 6 /C3 N4异质结在可见光照射下表现出优异且稳定的光催化NO净化能力，明显优于纯Cs2 SnCl 6和C3 N4。结合原位漫反射傅里叶变换红外光谱和电子自旋共振自旋捕获技术，揭示了Cs2 SnCl 6 /C3 N4光催化脱硝的机理.在可见光照射下，C3 N4导带上的光生电子自发迁移到Cs2 SnCl 6的CB上，在C3 N4的价带上留下空穴（h +），有效地分离了载流子，提高了光催化NO的净化效果.密度泛函理论计算还揭示了C3 N4和Cs2 SnCl 6界面上的定向电子转移，即内电场诱导电荷从C3 N4向Cs2 SnCl 6迁移。该研究为Cs2 SnCl 6 /C3 N4异质结的制备及其有效的界面电荷分离提供了新的思路。首次设计了无铅钙钛矿异质结Cs2 SnCl 6 /C3 N4光催化剂。·揭示了异质结界面之间的电子输运方向。·异质结具有高效稳定的光催化活性。·通过密度泛函理论和原位漫反射傅里叶变换红外光谱分析，揭示了光催化氧化NO的机理。
In this study, a novel lead-free perovskite heterojunction Cs 2 SnCl 6 /C 3 N 4 composite was constructed and applied for photocatalytic NO purification. After design optimization, the Cs 2 SnCl 6 /C 3 N 4 heterojunction exhibit excellent and stable photocatalytic NO purification ability under visible-light irradiation, which is significantly better than pristine Cs 2 SnCl 6 and C 3 N 4 . Combined in-situ DRIFTS and electron spin resonance spin-trapping, the mechanism of Cs 2 SnCl 6 /C 3 N 4 photocatalytic NO removal was revealed. Under visible-light irradiation, the photo-generated electrons on the conduction band of C 3 N 4 would spontaneously migrate to the CB of Cs 2 SnCl 6 , leaving holes (h + ) on the valence band of C 3 N 4 , contributing to efficiently segregated charge carriers and improved photocatalytic NO purification. Density functional theory calculations also revealed the directional electron transfer at the C 3 N 4 and Cs 2 SnCl 6 interface, in which the charge was migrated from C 3 N 4 to Cs 2 SnCl 6 induced by the internal electric field. This research sheds fresh light on the fabrication of Cs 2 SnCl 6 /C 3 N 4 heterojunctions as well as its effective interfacial charge separation. • Lead-free perovskite heterojunctions Cs 2 SnCl 6 /C 3 N 4 photocatalyst was designed for the first time. • The direction of electron transport between heterojunction interfaces is revealed. • Heterojunctions exhibit efficient and stable photocatalytic activity. • The mechanism of photocatalytic oxidation of NO was revealed by DFT and in-situ DRIFTS.