Dong Xiaoxi, Xu Yuelong, Wang Shasha, Zhao Junping, Ren Bin, Zhang Lihui, Liu Zhenfa
School of Chemical Engineering and Technology, Hebei University of Technology, Tianjin 300000, China.
Institute of Energy Resources, Hebei Academy of Sciences, Shijiazhuang 050081, China.
Materials (Basel). 2018 Nov 14;11(11):2271. doi: 10.3390/ma11112271.
Environmental problems caused by metal ions have caused widespread concern in recent years. In this work, carbon aerogels (CAs) adsorbing different metal ions were prepared. The adsorption performance and kinetics of metal ions (Cu(II), Cr(VI), and Fe(III)) on carbon aerogels were systematically investigated. The results indicated that the maximum adsorption capacity of Cu(II) was 424 mg·g in 600 mg·L copper solution. Adsorption performances of Cu(II), Cr(VI), and Fe(III) on CAs well fitted with a pseudo-second-order kinetic model. The structures and morphologies of metal-containing samples were characterized by scanning electron micrographs (SEM), Energy Dispersive Spectrometer (EDS), transmission electron microscope (TEM), and X-ray diffraction (XRD). The results demonstrated that the texture and electrochemical performance of CAs adsorbing metal ions exhibited a clear change. The specific surface area of CAs for adsorbing copper ions was 450 m²·g and they showed a small average pore diameter (7.16 nm). Furthermore, CAs adsorbing metals could be used for the super capacitor. The specific capacitance of CAs adsorbing copper ions could reach 255 F·g at a current density of 1.0 A·g. The CA-Cu electrode materials exhibited excellent reversibility with a cycling efficiency of 97% after 5000 cycles.
近年来，金属离子引起的环境问题已受到广泛关注。在本研究中，制备了吸附不同金属离子的碳气凝胶（CA）。系统研究了碳气凝胶对金属离子（Cu(II)、Cr(VI)和Fe(III)）的吸附性能及动力学。结果表明，在600 mg·L的铜溶液中，Cu(II)的最大吸附容量为424 mg·g。Cu(II)、Cr(VI)和Fe(III)在碳气凝胶上的吸附性能均符合准二级动力学模型。通过扫描电子显微镜（SEM）、能量色散谱仪（EDS）、透射电子显微镜（TEM）和X射线衍射（XRD）对含金属样品的结构和形貌进行了表征。结果表明，吸附金属离子的碳气凝胶的织构和电化学性能发生了明显变化。吸附铜离子的碳气凝胶的比表面积为450 m²·g，平均孔径较小（7.16 nm）。此外，吸附金属的碳气凝胶可用于超级电容器。在电流密度为1.0 A·g时，吸附铜离子的碳气凝胶的比电容可达255 F·g。CA-Cu电极材料表现出优异的可逆性，在5000次循环后循环效率为97%。
