1. Crystal phase-controlled synthesis of BiPO4 and the effect of phase structure on the photocatalytic degradation of gaseous benzene.
- Author
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Wang, Jinghui, Li, Jinze, Li, Hui, Duan, Shixiang, Meng, Sugang, Fu, Xianliang, and Chen, Shifu
- Subjects
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BISMUTH phosphate , *CHEMICAL decomposition , *WIDE gap semiconductors , *BENZENE analysis , *X-ray photoelectron spectroscopy - Abstract
As a typical wide-band-gap semiconductor, BiPO 4 (BPO) has a great potential for photocatalytical degradation of highly stable benzene (C 6 H 6 ) that has been regarded as a priority hazardous VOC substance in the indoor atmosphere. Hexagonal (H-BPO), monoclinic (M-BPO), and their mixture phase BiPO 4 (M/H-BPO) were selectively synthesized to study the effect of BPO phase structure on the degradation of C 6 H 6 . The samples were characterized by several techniques, including X-ray diffraction, FTIR spectroscopy, UV–vis diffuse reflection spectroscopy, N 2 absorption-desorption measurements, scanning/transmission electron microscopy, and X-ray photoelectron spectroscopy. The results indicated that the monoclinic phase was a thermodynamically stable phase. The band gap energy of H-BPO, M-BPO, and M/H-BPO was 3.74, 3.93 and 3.86 eV, respectively. A transformation from rice-like hexagonal BPO to monoclinic phase nanorods was realized through varying the hydrothermal temperature and the composition of the solvent. The degradation of C 6 H 6 was closely associated with the crystalline phase of BPO and the mineralization rates decreased in order of M– (7.3) > M/H– (1.51) > H-BPO (0.51 μmol·h −1 ·m −2 ). The rates were higher than that of well-known P25 (0.34 μmol·h −1 ·m −2 ). The highest activity of M-BPO could be ascribed to its intrinsic distortion of PO 4 tetrahedron and the largest band gap structure. OH, O 2 − , and photoinduced holes were the major oxidation species accounting for the destruction of C 6 H 6 . [ABSTRACT FROM AUTHOR]
- Published
- 2017
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