Hybrid Metal-Organic Framework-Reduced Graphene Oxide Nanomaterial for Selective Removal of Chromate from Water in an Electrochemical Process.
Hybrid Metal-Organic Framework-Reduced Graphene Oxide Nanomaterial for Selective Removal of Chromate from Water in an Electrochemical Process.
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DOI：
10.1021/acs.est.0c04703
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发表时间：
2020-09
影响因子：
11.4
通讯作者：
Kuichang Zuo;Xiaochuan Huang;Xingchen Liu;Eva Maria Gil Garcia;Jun Kim;Amit Jain;Long Chen;P. Liang;A. Zepeda;R. Verduzco;J. Lou;Qilin Li
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文献类型：
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作者：
Kuichang Zuo;Xiaochuan Huang;Xingchen Liu;Eva Maria Gil Garcia;Jun Kim;Amit Jain;Long Chen;P. Liang;A. Zepeda;R. Verduzco;J. Lou;Qilin Li
六价铬Cr（VI）是一种剧毒的地下水污染物。在这项研究中，我们展示了一种选择性的电化学过程，专门用于去除Cr（VI）使用纳米复合电极材料MOF@rGO合成的纳米晶，混合配体八面体金属有机框架与钴金属中心，[Co2（btec）（bipy）（DMF）2]n（Co-MOF），在还原氧化石墨烯（rGO）的表面上原位生长。rGO提供电极所需的导电性，而Co-MOF赋予CrO 42-高度选择性的吸附位点。当用作处理循环中的阳极时，MOF@rGO电极对CrO 42-的吸附表现出强的选择性，而竞争阴离子包括Cl-、SO 42-和As（III），并且由于Co-MOF对CrO 42-的强物理吸附而实现>100%的充电效率;当高毒性的Cr（VI）被降低到低毒性时，还原的Cr物质并随后释放到盐水中。这种方法允许容易再生的非导电的Co-MOF没有任何化学添加，同时转换Cr（VI），启发了一种新的电化学方法，用于高度选择性降解有毒污染物，使用定制设计的电极与高亲和力吸附剂。
Hexavalent chromium Cr(VI) is a highly toxic groundwater contaminant. In this study, we demonstrate a selective electrochemical process tailored for removal of Cr(VI) using a nanocomposite electrode material MOF@rGO synthesized by in situ growth of a nanocrystalline, mixed ligand octahedral metal-organic framework with cobalt metal centers, [Co2(btec)(bipy)(DMF)2]n (Co-MOF), on the surface of reduced graphene oxide (rGO). The rGO provides the electric conductivity necessary for an electrode, while the Co-MOF endows highly selective adsorption sites for CrO42-. When used as an anode in the treatment cycles, the MOF@rGO electrode exhibits strong selectivity for adsorption of CrO42- over competing anions including Cl-, SO42- and As(III), and achieves charge efficiency >100% due to the strong physisorption of CrO42- by Co-MOF; both electro- and physi- sorption capacity is regenerated with a reversal of the applied voltage, when highly toxic Cr(VI) is reduced to low toxicity, reduced Cr species and subsequently released into the brine. This approach allows easy regeneration of the nonconducting Co-MOF without any chemical addition while simultaneously transforms Cr(VI), inspiring a novel electrochemical method for highly selective degradation of toxic contaminants using tailor designed electrodes with high affinity adsorbents.