Construction of ZnFe2O4/rGO composites as selective magnetically recyclable photocatalysts under visible light irradiation
Construction of ZnFe2O4/rGO composites as selective magnetically recyclable photocatalysts under visible light irradiation
复制标题
可见光照射下构建 ZnFe2O4/rGO 复合材料作为选择性磁性可回收光催化剂
DOI：
10.1088/1361-6528/ab116a
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发表时间：
2019-08-02
期刊：
影响因子：
3.5
通讯作者：
Sheng, Jiawei
中科院分区：
文献类型：
--
作者：
Sun, Qing;Wu, Kun;Sheng, Jiawei
本文报道了用改进的溶胶凝胶法制备高活性的氧化锌/氧化石墨烯纳米复合材料。用X射线衍射仪、X射线光电子能谱等检测手段对所制备的样品进行了表征，结果表明，在rGO衬底上生长出了直径约为15 nm、约为50 nm的纳米氧化锌颗粒。以亚甲基蓝(MB)在可见光下的降解为指标，考察了ZnFe2O4/rGO催化剂的光催化活性。结果表明，所制得的ZnFe2O4/rGO催化剂具有较高的光催化活性，在180min内对MB的降解率接近100%。此外，ZnFe2O4/rGO催化剂对罗丹明B(RhB)和甲基橙(MO)也有较好的去除效果。机理研究表明，rGO起到了稳定剂的作用，阻止了ZnFe2O4的聚集，并改善了光生电子的分离。染料的高效降解归因于在ZnFe2O4/rGO催化剂上H-2O-的光化学分解产生羟基自由基(.OH)，从而导致染料的氧化。值得注意的是，ZnFe2O4/rGO催化剂在5次循环后仍然保持了90%以上的效率。X射线衍射仪、X射线光电子能谱和VSM表征表明，所制得的催化剂具有稳定的晶体结构，易于分离。
This paper reports on highly active ZnFe2O4/reduced graphene oxide (ZnFe2O4/rGO) nanocomposites synthesized by a modified sol-gel method. The as-prepared samples have been characterized by XRD, XPS and other detection methods, which demonstrate that ZnFe2O4 nanoparticles (NPs) with a diameter of 15 similar to 50 nm were densely grown on the rGO substrates. The photocatalytic activities of ZnFe2O4/rGO catalysts were evaluated by the degradation of Methylene blue (MB) under visible light. The results showed that the ZnFe2O4/rGO catalysts had high photocatalytic activity, and the degradation efficiency of MB was almost 100% within 180 min. Moreover, the ZnFe2O4/rGO catalysts also had a great removal effect on Rhodamine B (RhB) and Methyl orange (MO). Mechanistic studies revealed that the rGO acted as a stabilizer to prevent ZnFe2O4 from aggregation and improved the separation of photo-generated electrons. The high efficiency for dye degradation was attributed to the generation of hydroxyl radicals (.OH) via the photochemical decomposition of H-2 O-2 on ZnFe2O4/rGO catalysts, which was responsible for the oxidation of the dyes. Of note, the ZnFe2O4/rGO catalyst maintained an efficiency of over 90% after five cycles. The XRD, XPS and VSM characterization revealed that the ZnFe2O4/rGO catalysts had a stable crystal structure and can be easily separated.