Study on Fe2O3/g-C3N4 photocatalytic degradation of Rhodamine B
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摘要: 为了改善g-C3N4比表面积低等缺点, 通过高温热聚合法制备了三维(3D)多孔g-C3N4, 并通过与Fe2O3复合得到Fe2O3/g-C3N4催化剂, 提高其可见光响应. Fe2O3/g-C3N4在g-C3N4含量为900 mg、罗丹明B(Rhodamine B, RhB)浓度为20 mg·L–1、H2O2为15 mmol时脱色速率最快, 30 min可达到100%. 同时Fe2O3/g-C3N4对其他有机物也表现出较好的降解性能, 在30 min内对甲基橙(Methyl orange, MO)、四环素(Tetracycline, TC)的降解率分别达到80%和90%. 通过活性基团捕获实验探究Fe2O3/g-C3N4的光催化降解机制, 实验结果表明h+和·OH在Fe2O3/g-C3N4光催化降解有机物过程中起到主要作用.Abstract: In order to improve the low specific surface area of g-C3N4, three-dimensional (3D) porous g-C3N4 was prepared using high temperature thermal polymerization. Fe2O3/g-C3N4 catalyst was prepared by compositing the g-C3N4 with Fe2O3 to improve its visible light response. The decolorization rate of the Fe2O3/g-C3N4 catalyst reached 100% in 30 minutes with a g-C3N4 content of 900 mg, Rhodamine B (RhB) concentration of 20 mg·L–1, and H2O2 content of 15 mmol. The Fe2O3/g-C3N4 catalyst also demonstrated good performance in degrading other organics; the degradation rates of Methyl orange (MO) and Tetracycline (TC) reached 80% and 90%, respectively, in 30 minutes. This photocatalytic mechanism was explored by active group capture experiments, and the results show that h+ and ·OH play an important role in the progress of photocatalysis.
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Key words:
- g-C3N4 /
- Fe2O3 /
- Rhodamine B(RhB) /
- photocatalytic
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表 1 g-C3N4和Fe2O3/g-C3N4的比表面积分析
Tab. 1 Surface area analysis of g-C3N4 and Fe2O3/g-C3N4
样品 比表面积/(m2·g–1) 孔容/(cm3·g–1) 孔径/nm CN-1 61 0.35 2.98 CN-2 72 0.36 3.84 CN-3 72 0.36 3.84 CN-4 74 0.35 3.82 CN-5 74 0.35 3.83 -
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