Rational design 2D/2D BiOCl/H+Ti2NbO7- heterojunctions for enhanced photocatalytic degradation activity
Rational design 2D/2D BiOCl/H+Ti2NbO7- heterojunctions for enhanced photocatalytic degradation activity
复制标题
合理设计2D/2D BiOCl/H Ti2NbO7-异质结以增强光催化降解活性
DOI：
10.1016/j.apsusc.2020.146334
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发表时间：
2020
影响因子：
6.7
通讯作者：
Zou Zhigang
中科院分区：
文献类型：
--
作者：
Gao Xin;Feng Yue;Dong Pengyu;Zhang Beibei;Chen Ting;Chen Xiaowei;Liu Chao;Xi Xinguo;Zou Zhigang
实现有机污染物的高效去除是环境与能源科学研究的热点。本文首先利用水热法制备了H+Ti2NbO7−(HTN)纳米片，制备了新型二维(2D)-2D BiOCl/H+Ti2NbO7−(BHT)异质结。HTN与BiOCl纳米板紧密结合，形成异质结构。以罗丹明B （rhodamine B, RhB）分子为目标污染物，评价样品在可见光下的光催化性能。与单一BiOCl和HTN相比，以BHT-4为最优样品的BHT复合材料对RhB的光催化活性均有所提高。活性的增强主要是由于BiOCl和HTN之间形成异质结，从而实现了有效的电荷分离和转移。所产生的活性物质可以通过俘获实验和ESR光谱检测到。结果表明，空穴（h+）和超氧自由基（dotO2−）在光催化降解RhB中起关键作用，羟基自由基（dotOH）起次要作用。根据实验结果，讨论了可能的光降解机理。这项工作为制备具有高光催化活性的2D/2D异质结提供了新的思路。
To realize highly efficient removal of organic pollutant is a hot spot in environmental and energy science. Herein, we firstly prepared re-stacked H+Ti2NbO7−nanosheets (HTN) to fabricate the novel two-dimensional (2D)-2D BiOCl/H+Ti2NbO7−(BHT) heterojunctions by a hydrothermal method. The HTN were well combined with BiOCl nanoplates with an intimate interface to form a heterostructure. The rhodamine B (RhB) molecules were used as a target pollutant to evaluate the photocatalytic performance of samples under visible light. All BHT composites, with an optimal sample of BHT-4, showed the improved photocatalytic activity for degradating RhB compared with the single BiOCl and HTN. The enhanced activity was mainly attributed to the efficient charge separation and transfer, which was resulted from the formation of heterojunction between BiOCl and HTN. The produced active species can be detected by trapping experiments and ESR spectra. It indicated that hole (h+) and superoxide radical (radical dotO2−) played a crucial role in the photocatalytic RhB degradation, while hydroxyl radical (radical dotOH) contributed a little. A possible photodegradation mechanism was also discussed based on the corresponding experimental results. This work provides an insight for preparing 2D/2D heterojunctions with a high photocatalytic activity.