Natural and synthetic adsorbents are used to remove contaminants from polluted waters. In particular, polymer-based aerogels are promising but their adsorption capacity and dimensional stability should be improved. Here we propose a new design strategy to prepare a dual-network aerogel, consisting of physical cross-linked agar and Ca²⁺ cross-linked sodium alginate as the first and second networks, respectively. After introducing cross-linked sodium alginate into the agar matrix, the morphology of the agar aerogel transformed from a distinct layered structure to a co-continuous network. The swelling degree ratio of the agar aerogel is reduced, and the dimensional stability was improved by introducing ion cross-linked sodium alginate into the agar matrix. The aerogels were used as adsorbents to remove methylene blue from aqueous solutions. The adsorption capacity of the agar aerogel was remarkably improved by adding sodium alginate due to the increase in electrostatic attraction and adsorption site.

中文翻译：

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通过引入原位离子交联的藻酸盐来增强琼脂气凝胶吸附剂性能的双网络设计

天然和合成吸附剂用于去除污水中的污染物。特别地，基于聚合物的气凝胶是有前途的，但是它们的吸附能力和尺寸稳定性应得到改善。在这里，我们提出了一种新的设计策略来制备由物理交联琼脂和Ca ²⁺组成的双网络气凝胶交联海藻酸钠分别作为第一和第二网络。将交联的海藻酸钠引入琼脂基质后，琼脂气凝胶的形态从明显的分层结构转变为共连续网络。通过将离子交联的藻酸钠引入琼脂基质中，降低了琼脂气凝胶的溶胀度比，并改善了尺寸稳定性。气凝胶用作吸附剂以从水溶液中除去亚甲基蓝。由于静电引力和吸附位点的增加，加入海藻酸钠可显着提高琼脂气凝胶的吸附能力。