生物质碳气凝胶/MnO2复合电极对 Rb+、Cs+的电吸附行为

以柚子皮为主要原料，采用低温水热碳化-真空冷冻干燥-高温碳化相结合的方法，制备了生物质碳气凝胶（PCA），并将其用于制备PCA单一和PCA@MnO2（MPCA）复合电吸附电极，利用SEM、XRD、FT-IR、BET及电化学工作站对电极材料的形貌、结构和电化学性质进行了表征，并考察了两种电极对Rb+、Cs+的电吸附行为。结果表明，自制PCA为三维多孔结构，利于吸附质扩散；电极比电容大，循环性能好。电极的组成对电吸附行为具有较大的影响，二氧化锰的加入改变了电极对离子的吸附选择性，MPCA［m（二氧化锰）∶m（PCA）=4∶1］复合电极对铷的吸附量明显优于铯，平衡吸附量分别可以达到85 μmol/g和64 μmol/g，优于PCA电极，且具有良好的循环再生性能。

Study of electrosorption of Rb+ and Cs+ by biomass carbon aerogel/MnO2 composite electrode

The biomass carbonaceous aerogel (PCA) was prepared through low temperature hydrothermal carbonization，vacu um freezedrying and high temperature carbonization method by using pomelo peel as main raw material.Then two types of electrosorption electrodes，biomass carbonaceous aerogel（PCA） and PCA composited with MnO2（MPCA） were synthesized and their morphology，structure and electrochemical properties were characterized by SEM，XRD，FT-IR，BET and electro chemical workstation.The electroadsorption performance of these two electrodes for Rb+ and Cs+ was investigated.The results showed that the selfmade PCA with three dimensional porous structure that was beneficial to the diffusion of adsorbates.Both the two electrodes have high specific capacitance and good cycle performance.The composition of the electrode had a signifi cant effect on its electrosorption behavior.The addition of MnO2 changed the adsorption selectivity of the ions.Compared with PCA electrode，MPCA ［m（MnO2）∶m（PCA）=4∶1］ electrode adsorbs Rb more than Cs，and the adsorption capacity can reach 85 μmol/g and 64 μmol/g，respectively，with good regeneration performance.