Bulk Al-doped carboxymethyl cellulose aerogels were obtained via a facile slow-gel method and freeze-drying technology. In this method, the cross-linker Al³⁺ was released slowly and completely with enough D-(+)-gluconic acid δ-lactone as a sustained-release agent. Depended on controlled releasing of Al³⁺, the reaction speed between Al³⁺ and carboxyl groups was controlled and Al³⁺ was well-distributed in the aerogels. The coordination type between Al³⁺ and carboxymethyl cellulose was the bidentate bridging coordination. By adjusting the amount of Al³⁺ and the degree of substitution of carboxymethyl cellulose, interconnected network and closely packed sheet-like structure presented, respectively. According to the nitrogen adsorption-desorption isotherms, the aerogels were a kind of mesoporous material with pore blocking or cavitation. In addition, the aerogels exhibited outstanding weight-bearing capacity and excellent flame retardancy. This work provided a valuable reference for doping metal ions into polysaccharide aerogels and expanding the application fields of aerogels.

通过简便的慢凝胶法和冷冻干燥技术获得了大量的铝掺杂羧甲基纤维素气凝胶。在该方法中，交联剂Al ³⁺缓慢而完全地释放，同时有足够的D-（+）-葡萄糖酸δ-内酯作为缓释剂。取决于Al ^3+的控制释放，控制了Al ³⁺与羧基之间的反应速度，并且Al ³⁺在气凝胶中分布良好。Al ³⁺与羧甲基纤维素之间的配位类型为双齿桥联配位。通过调整Al ³⁺的含量分别给出了羧甲基纤维素的取代度，互连网络和紧密堆积的片状结构。根据氮的吸附-解吸等温线，气凝胶是一种具有孔阻塞或空化作用的中孔材料。另外，气凝胶显示出优异的承重能力和优异的阻燃性。这项工作为将金属离子掺杂到多糖气凝胶中并扩展气凝胶的应用领域提供了有价值的参考。