Huang Xiaohui, Li Yuewei, Yin Xianglu, Tian Jie, Wu Wei
Research Center of the Ministry of Education for High Gravity of Engineering and Technology , Beijing University of Chemical Technology , Beijing 100029 , China.
Langmuir. 2019 Oct 29;35(43):13833-13843. doi: 10.1021/acs.langmuir.9b02236. Epub 2019 Oct 17.
In this study, a simple, effective, and versatile method was used for the exfoliation of kaolinite by high-shear mixer with graphite oxide as an an amphiphilic dispersant. During the liquid-phase exfoliation process, the co-exfoliation of kaolinite and graphite oxide was realized. Compared with the directly exfoliated kaolinite, when 5% graphite oxide was added to facilitate exfoliation, 95% of the obtained nanosheets were distributed between 0.1 and 0.7 μm, in which the number of layers was less than 5, and part of them were curled into nanoscrolls structure with a length of 0.2-0.9 μm. The Brunauer-Emmett-Teller surface area of the graphite oxide assisted exfoliated kaolinite was 2.1 times that of the directly exfoliated kaolinite. Meanwhile, the graphite oxide assisted exfoliated kaolinite exhibited excellent adsorption properties for MB, whose theoretical maximum adsorption capacity was 250 mg/g, significantly higher than that of the directly exfoliated kaolinite, which was about 111 mg/g. It has been verified that the exfoliation method is efficient and facile and can be applied extensively.
在本研究中,采用了一种简单、有效且通用的方法,以氧化石墨作为两亲性分散剂,通过高剪切混合器对高岭土进行剥离。在液相剥离过程中,实现了高岭土与氧化石墨的共剥离。与直接剥离的高岭土相比,当添加5%的氧化石墨以促进剥离时,所获得的纳米片中有95%分布在0.1至0.7μm之间,其中层数小于5层,部分卷曲成长度为0.2 - 0.9μm的纳米卷轴结构。氧化石墨辅助剥离的高岭土的布鲁诺尔-埃米特-特勒(Brunauer-Emmett-Teller)比表面积是直接剥离的高岭土的2.1倍。同时,氧化石墨辅助剥离的高岭土对亚甲基蓝(MB)表现出优异的吸附性能,其理论最大吸附容量为250mg/g,显著高于直接剥离的高岭土,后者约为111mg/g。已证实该剥离方法高效且简便,可广泛应用。