摘要
以生物质碳为碳源,以SiO2和Si混合粉体为硅源,通过控制碳热还原合成的工艺条件分别合成了SiC微球、SiC/SiO2纳米串珠和SiC纳米线等.借助XRD、SEM及TEM等测试手段分析了三种纳米结构SiC材料的相组成及微观结构,并采用可见光催化分解亚甲基蓝溶液评估了三种纳米结构SiC材料的光催化性能.研究结果表明：SiC微球由SiC纳米颗粒组成、SiC/SiO2纳米串珠由SiC纳米线作为芯轴,非晶SiO2包覆在SiC纳米线外形成周期性的串珠结构;三种纳米结构SiC材料在300~800nm的可见光范围内均有较强的吸收能力.SiC/SiO2纳米串珠的表层SiO2可以有效分离光生电子-空穴,且SiO2层表面富集的羟基自由基更有利于光催化降解有机物的发生,提高了其催化效率,故SiC/SiO2纳米串珠较SiC微球和SiC纳米线具有更好的可见光催化能力.
Based on biomass carbon as carbon source,SiO2 and Si mixed powder as silicon source,SiC microspheres,SiC/SiO2 nanochains and SiC nanowires were prepared by controlling the carbon thermal reduction.The phase and microstructure of the prepared nanostructures SiC are investigated by X-ray diffraction（XRD）,scanning electron microscopy（SEM）and transmission electron microscopy（TEM）.The visible-light photocatalytic activity of the nanostructures SiC is evaluated by photocatalytic degradation of the methylene blue solution.Results show that the SiC microspheres are composed of SiC nanoparticles.The SiC/SiO2 nanochains are made up of the SiC core line and the amorphous SiO2 forming aperiodic structure bead.The prepared nanostructures SiC present a strong absorbance in the visible-light range of 300~800nm.The photocatalytic activity of SiC/SiO2 nanochains are found to be better compared to that of the SiC microspheres and SiC nanowires,which is due to the amorphous SiO2 that can form activated hydroxyl groups and effectively separate the photogenerated electrons and holes.
出处
《陕西科技大学学报（自然科学版）》
2015年第4期45-50,共6页
Journal of Shaanxi University of Science & Technology
基金
国家自然科学基金项目(51402177)
陕西省科技厅自然科学基础研究计划项目(2014JQ6213)
陕西科技大学博士科研启动基金项目(BJ14-20)
关键词
纳米结构SiC
微观结构
光催化性能
nanostructures SiC
microstructure
photocatalytic activity
