Realization of of super high adsorption capability of 2D δ-MnO2/GO through intra-particle diffusion
Realization of of super high adsorption capability of 2D δ-MnO2/GO through intra-particle diffusion
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DOI：
10.1016/j.matchemphys.2019.05.004
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发表时间：
2019-06-15
影响因子：
4.6
通讯作者：
Gao, Meizhen
中科院分区：
文献类型：
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作者：
Jiang, Subin;Yu, Tengfei;Gao, Meizhen
由于其高比表面积和独特的孔隙性质，二维材料在吸附中具有广阔的应用前景。本文通过一步自组装法合成了二维delta-MnO2，并研究了其对亚甲基蓝（MB）的吸附性能。最大吸附量达到267.6 mg/g，远远超过以往报道的类似结构的吸附剂。考虑到氧化石墨烯的独特性质，将制备的二维二氧化锰与氧化石墨烯结合，进一步提高其吸附能力。复合后的化合物表现出超高的吸附能力，2D delta-MnO2/GO对MB的吸附量增加到1432.0 mg/g，是2D delta-MnO2吸附量的5倍以上，吸附量的显著增加是由于孔径的增大，开启了颗粒内扩散通道。用拟二阶模型和Langmuir等温线模型分别分析了二维MnO2和二维δ -MnO2/GO在不同平衡浓度下的吸附动力学和吸附等温线。
Due to the high specific surface area and unique pore properties, two-dimensional materials (2D) are promising candidates in adsorption. In this work, 2D delta-MnO2 is synthesized through one-step self-assembly and its adsorption properties to methylene blue (MB) are examined. The maximum adsorption amount achieved 267.6 mg/g, it is far high beyond adsorbents reported previously which have similar structures. Considering the unique properties of GO, the prepared 2D MnO2 is combined with GO to enhance the adsorption capacities further. The combined compounds exhibit super high adsorption capabilities and the adsorption amount of 2D delta-MnO2/GO to MB increased to 1432.0 mg/g, which is more than 5 times higher than that of 2D delta-MnO2, the significant increase of adsorption amount is owing to the increase of pore size, which initiates the intra-particle diffusion channel. The adsorption kinetics and adsorption isotherms of 2D MnO2 and 2D delta-MnO2/GO are also analyzed with pseudo-second-order model and Langmuir isotherm model at different equilibrium concentration respectively.