Enhancement mechanism of fiddlehead-shaped TiO2-BiVO4 type II heterojunction in SPEC towards RhB degradation and detoxification
Enhancement mechanism of fiddlehead-shaped TiO2-BiVO4 type II heterojunction in SPEC towards RhB degradation and detoxification
复制标题
SPEC中蕨形TiO2-BiVO4 II型异质结对RhB降解和解毒的增强机制
DOI：
10.1016/j.apsusc.2018.08.239
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发表时间：
2019-01-01
影响因子：
6.7
通讯作者：
Yuan, Xing
中科院分区：
文献类型：
--
作者：
Wang, Yaqi;Lu, Nan;Yuan, Xing
采用改进的溶胶-凝胶-水热法设计了用于太阳能光电催化(SPEC)的II类异质结TiO2BiVO4复合薄膜，以抑制电子和空穴的复合，扩大光吸收范围。纤头状颗粒具有更大的比表面积(157.63 m(2)·g(-1))和更高的捕光效率。与光催化(PC)体系(79.3%)相比，SPEC体系对RhB的降解率显著提高到93.9%。通过能带调整、主要活性基团测定和量子化学计算，进一步探讨了SPEC体系的增强机理和退化途径。此外，利用费氏弧菌对RhB及其降解产物进行了急性生态毒性试验。在SPEC体系中，其生态毒性几乎完全消除，而在PC体系中，其生态毒性增加。纳米复合膜还表现出良好的可回收性和稳定性，可以大大降低经济成本，限制二次污染的可能性。因此，TiO2BiVO4纳米复合膜具有很大的应用潜力，为有机废水的处理提供了一种可持续、无害的技术。
Type II heterojunction TiO2-BiVO4 composite films were designed via modified sol-gel-hydrothermal method for solar photoelectrocatalysis (SPEC) to restrain the recombination of electrons and holes as well as expand light absorption range. Fiddlehead-shaped morphology resulted in a larger specific surface area (157.63 m(2).g(-1)) and an intensification of light-harvesting efficiency. In comparison with photocatalytic (PC) system (79.3%), the degradation efficiency of RhB increased significantly to 93.9% in SPEC system. The enhancement mechanism and degradation path of SPEC systems was further discussed based on energy band adjustment, main active group determination, and quantum chemical calculation. Furthermore, the acute ecotoxicity of RhB and its degradation products were tested by Vibrio fischeri. The ecotoxicity was almost completely eliminated in SPEC system but it increased in PC system. The nanocomposite film also represented an excellent recyclability and stability, which may greatly reduce the economic cost and limit the probability of secondary pollution. Therefore, TiO2-BiVO4 nanocomposite films exhibited great potential in SPEC, providing a sustainable and harmless technique to treat organic wastewater.