Fe_(3)O_(4)-BiOBr/Graphene磁性气凝胶的构筑与Cr(VI)污水净化  

Construction of magnetic Fe_(3)O_(4)-BiOBr/Graphene aerogel and Cr(VI)wastewater purification

作　　者：铁伟伟[1] 邱帅彪 王红霞 袁双义 董旭 何伟伟[1] TIE Weiwei;QIU Shuaibiao;WANG Hongxia;YUAN Shuangyi;DONG Xu;HE Weiwei(Key Laboratory of Micro-Nano Materials for Energy Storage and Conversion of Henan Province,Institute of Surface Micro and Nano Materials,College of Chemical and Materials Engineering,Xuchang University,Xuchang 461000,China)

机构地区：[1]许昌学院化工与材料学院(表面微纳米材料研究所),河南省微纳米能量储存与转换材料实验室,许昌461000

出　　处：《复合材料学报》2024年第4期1987-1996,共10页Acta Materiae Compositae Sinica

基　　金：河南省国家级大学生创新创业训练项目(202110480014);河南省高等学校青年骨干教师培养计划(2021GGJS145);河南省高等学校重点科研项目(22A430036)。

摘　　要：为改善单一半导体粉体材料的光生电子-空穴分离和回收能力,基于功能协同效应,采用共沉淀法,将Fe^(3+)/Fe^(2+)盐在一定浓度的氨水作用下制备出纳米Fe_(3)O_(4),并分散于含有溴化十六烷基三甲铵(CTAB)的正辛烷中,提供Br-的同时,在室温下与水溶液中的硝酸铋和柠檬酸相互作用,利用非互溶体系,制备出Fe_(3)O_(4)-BiOBr;最后,将Fe_(3)O_(4)-BiOBr分散于含有赖氨酸的氧化石墨烯水溶液中,通过一步水热法合成Fe_(3)O_(4)-BiOBr协同修饰的磁性石墨烯气凝胶(Fe_(3)O_(4)-BiOBr/Graphene)。样品的晶体结构、形貌特征和催化活性通过XRD、Raman、XPS、SEM、TEM、UV-Vis光谱等综合测试技术进行了表征分析。Fe_(3)O_(4)-BiOBr/Graphene复合材料中的Fe_(3)O_(4)呈类球状,尺寸约10~25 nm,均匀镶嵌于BiOBr片层中间,并与石墨烯之间相互作用,整体呈现球-片-空洞构造。Fe_(3)O_(4)-BiOBr/Graphene复合材料显示出良好的可见光吸收性和Cr(VI)还原活性,30 min内可去除Cr(VI)至100%,高于单一组分的磁性Fe_(3)O_(4),这可能与Fe_(3)O_(4)-BiOBr异质结构、石墨烯导电材料的引入及Fe_(3)O_(4)-BiOBr/Graphene三者之间良好的界面相互作用,有效地促进了光生电子与空穴的分离效率有关。In order to improve the photogenerated electron-hole separation and recycling ability of single semiconductor powder material,based on the functionally synergistic effect,magnetic graphene aerogel(Fe_(3)O_(4)-BiOBr/graphene)modified by Fe_(3)O_(4)-BiOBr had been facilely prepared by one-step hydrothermal process by dispersing Fe_(3)O_(4)-BiOBr composite in aqueous solution of graphene oxide containing lysine.The Fe_(3)O_(4)-BiOBr composite was synthesized in non-miscible solvent system under room-temperature,in which nano Fe_(3)O_(4),firstly prepared by co-precipitation method using Fe3+/Fe2+salt under the action of ammonia water with a certain concentration,was dispersed in n-octane containing hexadecyl trimethyl ammonium bromide(CTAB)for providing Br-,interacting with an aqueous solution containing bismuth nitrate and citric acid adding drop by drop.The crystal structure,morphology and catalytic activity of the samples were characterized by XRD,Raman,XPS,SEM,TEM,and UV-Vis spectra.Fe_(3)O_(4)-BiOBr/graphene composites,in which spherical Fe_(3)O_(4)with a size of 10-25 nm are evenly embedded in layered BiOBr flakes,and they interact with graphene,overall,have showed a sphere-sheet-cavity structure.Fe_(3)O_(4)-BiOBr/graphene composites have favorable visible light absorption efficiency and Cr(VI)photocatalytic activity.The photocatalytic activity of Cr(VI)could achieve about 100%within 30 min,which is higher than that of single magnetic Fe_(3)O_(4).This phenomenon maybe origin from the introduction of Fe_(3)O_(4)-BiOBr heterostructure and conductive graphene as well as their good interfacial interaction within them,effectively promoting the separation efficiency of photogenerated electrons and holes between Fe_(3)O_(4)-BiOBr/graphene composite.

关 键 词：溴氧化铋 四氧化三铁 石墨烯气凝胶 六价铬 磁性回收 光催化还原 

分 类 号：O614.24[理学—无机化学] TB333[理学—化学]