一步法制备石墨烯复合花状钨酸铋光催化剂

doi:10.15541/jim20140069

摘要/Abstract

摘要：

采用一步水热法合成石墨烯复合花状钨酸铋高效可见光光催化剂。降解甲基橙的性能实验结果表明, 与单纯的Bi₂WO₆相比, 所有Bi₂WO₆-rGO复合光催化剂表现出更高的光催化性能。其中, Bi₂WO₆-rGO (0.5wt%)具有最高的光催化活性, 其速率常数达到5.0×10^-2/min, 是纯Bi₂WO₆的1.7倍。增强光催化性能的原因归结为以下两方面的协同作用: 还原石墨烯在复合光催化剂中起到了电子快速传输作用; 石墨烯提供了有利于吸附有机污染物的大比表面积。本研究可以为设计与合成高性能石墨烯基光催化剂提供新的思路。

关键词: 钨酸铋, 石墨烯, 石墨烯复合钨酸铋光催化剂, 可见光光催化性能

Abstract:

A one-step hydrothermal method was developed for fabrication of flower-like Bi₂WO₆-rGO composite photocatalysts with high-efficiency visible-light photocatalytic activity. Photocatalytic experimental results for the decolorization of methyl orange (MO) aqueous solution indicated that all the resulted Bi₂WO₆-rGO photocatalysts exhibited a much higher photocatalytic performance than the pure Bi₂WO₆, and the Bi₂WO₆-rGO (0.5wt%) showed the highest photocatalytic activity with a k = 5.0×10^-2/min, a value as 1.7 times as that of the pure Bi₂WO₆. The enhanced performance can be attributed to the cooperation effect of rGO nanosheet which promoted the effective transfer of photogenerated electrons and provided large surface area for absorbing organic pollutants. This work may provide new insights into design and fabrication of high-performance graphene-based photocatalytic materials.

Key words: Bi2WO6, graphene, Bi2WO6-rGO composite photocatalysts, visible-light photocatalytic activity

中图分类号:

O643

郭丹, 王苹, 郑琪颖, 王进. 一步法制备石墨烯复合花状钨酸铋光催化剂[J]. 无机材料学报, 2014, 29(11): 1193-1198.

GUO Dan, WANG Ping, ZHENG Qi-Ying, WANG Jin. One-step Synthesis of Flower-like Bi₂WO₆-rGO Composite Photocatalysts[J]. Journal of Inorganic Materials, 2014, 29(11): 1193-1198.

图/表 10

图1 Bi2WO6-rGO合成示意图(A)和样品照片(B)

Fig. 1 Graphical illustration for the synthesis of Bi2WO6-rGO nanocomposite (A) and photographs of various samples(B) (1) GO solution; (2,3) Bi2WO6-GO suspension before (2) and after(3) aging for 5 min; (4,5) Bi2WO6 suspension before (4) and after (5) aging for 5 min; (6,7) Bi2WO6-rGO suspension before (6) and after (7) aging for 5 min

图2 不同样品的XRD图谱

Fig. 2 XRD patterns of different samples (a) GO; (d) rGO; (c) Bi2WO6; (d) Bi2WO6-rGO (0.5wt%)

图3 不同样品的场发射扫描电镜照片

Fig. 3 FESEM images of different samples (a) GO; (b,c) Bi2WO6; (d,e,f) Bi2WO6-rGO (0.5wt%)

图4 不同样品的红外光谱图

Fig. 4 FTIR spectra of different samples (a) GO; (b) rGO; (c) Bi2WO6; (d) Bi2WO6-rGO (0.5wt%)

图5 不同样品的拉曼光谱图

Fig. 5 Raman spectra of different samples (a) GO; (b) rGO; (c) Bi2WO6; (d) Bi2WO6-rGO (0.5wt%)

图6 不同样品的紫外漫反射光谱

Fig. 6 UV-Vis diffuse re?ectance spectra of different samples (a) Bi2WO6 ; (b) Bi2WO6-rGO(0.5wt%)

图 7 催化剂降解甲基橙的速率常数

Fig. 7 Rate constant (k) of the MO decomposition by various photocatalysts (a) Bi2WO6; (b) Bi2WO6-rGO (0.1wt%); (c) Bi2WO6-rGO (0.5wt%); (d) Bi2WO6-rGO (1wt%); (e) Bi2WO6-rGO(5wt%)

图 8 Bi2WO6-rGO (0.5wt%)降解甲基橙循环性能图

Fig. 8 Cycling performance of Bi2WO6-rGO (0.5wt%) for the degradation of MO

图9 Bi2WO6- rGO光催化机理示意图

Fig. 9 Schematic diagram for illuminating the photocatalytic mechanism of Bi2WO6-rGO

图10 不同样品的荧光光谱图

Fig. 10 Photoluminescence (PL) spectra of different samples (a) Bi2WO6 and ----b) Bi2WO6-rGO (0.5wt%)

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