Hydrothermal synthesis of m-BiVO
4/t-BiVO
4 heterostructure for organic pollutants degradation: Insight into the photocatalytic mechanism of exposed facets from
crystalline phase controlling.
JOURNAL OF HAZARDOUS MATERIALS 2020;
399:123159. [PMID:
32937728 DOI:
10.1016/j.jhazmat.2020.123159]
[Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/24/2019] [Revised: 06/05/2020] [Accepted: 06/05/2020] [Indexed: 06/11/2023]
Abstract
A series of BiVO4 photocatalysts were prepared by a co-precipitation followed hydrothermal synthesis method for the photodegradation of Rhodamine B (RhB) and 2,4-Dichlorophenol (2,4-DCP). The crystalline phase ratio of the heterostructured BiVO4 (m-BiVO4/t-BiVO4) between monoclinic and tetragonal could be easily controlled at different pH and hydrothermal time. Interestingly, the as-prepared heterostructured BiVO4 photocatalyst at pH = 7 for 24 h (BiVO4-7-24) showed the highest photocatalytic activities for the degradation of RhB, while the best photodegradation of 2,4-DCP was obtained at pH = 0.5 for 24 h (BiVO4-0.5-24). The photocatalytic mechanism can be explained by the different charge carrier transfer pathways and active oxidation species in the m-BiVO4/t-BiVO4 heterostructure. More importantly, the exposed facets originated from crystalline phase controlling in BiVO4-0.5-24 and BiVO4-7-24 photocatalyst is an essential reason for the different photocatalytic activity. The proposed energy band alignments of BiVO4-0.5-24 and BiVO4-7-24 photocatalyst provide insights into the photocatalytic mechanism of the m-BiVO4/t-BiVO4 heterostructure.
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