Yang Jia, Sun Xiaorui, Zeng Chunmei, Wang Xiaoting, Hu Yilan, Zeng Ting, Shi Jianwei
Chongqing Key Laboratory of Inorganic Special Functional Materials, College of Chemistry and Chemical Engineering, Yangtze Normal University Fuling Chongqing 408100 P. R. China
Chemical Synthesis and Pollution Control Key Laboratory of Sichuan Province, College of Chemistry and Chemical Engineering, China West Normal University Nanchong 637002 P. R. China.
RSC Adv. 2019 Aug 28;9(46):26894-26901. doi: 10.1039/c9ra04632a. eCollection 2019 Aug 23.
In this work, BiGa Fe O (0 ≤ ≤ 1.2) solid solutions were prepared the traditional high-temperature solid-state reaction. The Le Bail fitting on the powder X-ray diffraction patterns shows that these solid solutions were successfully synthesized. Scanning electron microscopy showed that the BiGaFeO sample was composed of sub-micron particle crystallites. Energy dispersive spectroscopy analysis and X-ray photoelectron spectroscopy were used to identify that the Fe element is trivalent when doping into the crystal structure. Ultraviolet-visible diffused reflectance spectra suggested that the bandgap of BiGaFeO is narrower than that of the undoped BiGaO sample. Three strategies, including Fe doping, addition of HO, and loading of the cocatalyst, were utilized to improve the photocatalytic degradation activity. The optimum photocatalytic performance was obtained over 2.5 wt% Cu/BiGaFeO sample in 20 ppm RhB aqueous solution (containing 1.5 mL HO) under visible light irradiation. Its photodegradation rate is 8.0 times that of BiGaO containing 0.5 mL HO. The 2.5 wt% Cu/BiGaFeO photocatalyst remained stable and active even after four cycles. Also, its photocatalytic conversion efficiency for RhB was nearly 100%, which was achieved in 3 hours. The photocatalytic mechanism indicated that ·OH and h played an important role in the photocatalytic degradation reaction.
在本工作中，采用传统高温固相反应法制备了BiGaFeO（0≤≤1.2）固溶体。对粉末X射线衍射图谱进行的勒拜尔拟合表明，这些固溶体已成功合成。扫描电子显微镜显示，BiGaFeO样品由亚微米级晶粒组成。利用能量色散光谱分析和X射线光电子能谱确定，Fe元素在掺杂进入晶体结构时为三价。紫外-可见漫反射光谱表明，BiGaFeO的带隙比未掺杂的BiGaO样品窄。采用了三种策略来提高光催化降解活性，包括Fe掺杂、添加H₂O₂和负载助催化剂。在可见光照射下，2.5 wt% Cu/BiGaFeO样品在20 ppm罗丹明B水溶液（含1.5 mL H₂O₂）中获得了最佳光催化性能。其光降解速率是含0.5 mL H₂O₂的BiGaO的8.0倍。即使经过四个循环，2.5 wt% Cu/BiGaFeO光催化剂仍保持稳定和活性。此外，其对罗丹明B的光催化转化效率接近100%，这在3小时内即可实现。光催化机理表明，·OH和h⁺在光催化降解反应中起重要作用。
