Phenolic compounds are persistent organic pollutants that endanger the environment and human health. To reduce phenol contamination, an oxidation-resistant MXene/poly(N-isopropylacrylamide) (PNIPAM) hydrogel thermosensitive adsorbents was prepared, which displayed excellent adsorption properties, good mechanical properties, and no secondary pollution. By using the 2-cyanoethyltriethoxysilane (CTES) as a bridge, (6-tetraethylenepentamine-6-deoxy) -β-cyclodextrin (NH-β-CD) was grafted onto the MXene surface to obtain NH-β-CD encapsulated MXene (MXene-CTES-β-CD). We exploit this cyclodextrin encapsulation method to simultaneously improve the antioxidant properties and the number of active groups of MXene. A thermosensitive adsorbent was prepared by in-situ polymerization of MXene-CTES-β-CD incorporated into N-isopropylacrylamide (NIPAM) and polymerized to obtain cyclodextrin-encapsulated-MXene/PNIPAM (MXene-CTES-β-CD/PNIPAM) thermosensitive adsorbents. The hydrogel adsorbent exhibited excellent oxidation resistance and no significant changes were observed even after 500 h of swelling in water. It also has excellent mechanical properties and could return to their original states from strains of 95%. Compared with the maximum capacity of the MXene/PNIPAM and MXene-CTES-COOH/PNIPAM hydrogels of 141 and 136 mg·g⁻¹, the adsorption capacity of the MXene-CTES-β-CD/PNIPAM hydrogel increased, and the effective adsorption of phenols with the maximum capacity of 162 mg·g⁻¹ for 4-NP under room temperature conditions. The hydrogel still has a high removal rate of its initial value 82% after five adsorption–desorption cycles, and the entire desorption process could be completed in distilled water at 35 °C not produce secondary contamination. Therefore, MXene-CTES-β-CD/PNIPAM thermosensitive adsorbents with high adsorption capacity, oxidation resistance, and no secondary pollution, which reveals prospects for sewage disposal. It is believed that this work indicates a new way to improve the oxidation resistance of MXenes.

酚类化合物是危害环境和人类健康的持久性有机污染物。为减少苯酚污染，制备了一种抗氧化的MXene/聚（N-异丙基丙烯酰胺）（PNIPAM）水凝胶热敏吸附剂，该吸附剂具有优异的吸附性能、良好的力学性能、无二次污染。以2-氰乙基三乙氧基硅烷（CTES）为桥梁，将（6-四亚乙基五胺-6-脱氧）-β-环糊精（NH-β-CD）接枝到MXene表面，得到NH-β-CD包封的MXene（MXene） -CTES-β-CD)。我们利用这种环糊精封装方法同时提高 MXene 的抗氧化性能和活性基团的数量。原位制备热敏吸附剂将 MXene-CTES-β-CD聚合到N-异丙基丙烯酰胺 (NIPAM) 中并聚合以获得环糊精封装的-MXene/PNIPAM (MXene-CTES-β-CD/PNIPAM) 热敏吸附剂。水凝胶吸附剂表现出优异的抗氧化性，即使在水中溶胀 500 小时后也没有观察到显着变化。它还具有出色的机械性能，可以在 95% 的应变下恢复到原始状态。与 MXene/PNIPAM 和 MXene-CTES-COOH/PNIPAM 水凝胶的最大容量 141 和 136 mg·g ^{-1 相比}，MXene-CTES-β-CD/PNIPAM 水凝胶的吸附容量增加，有效吸附最大容量为 162 mg·g ^-1的酚类对于室温条件下的 4-NP。经过5次吸附-解吸循环后，水凝胶仍具有初始值82%的高去除率，整个解吸过程可在35℃蒸馏水中完成，不会产生二次污染。因此，MXene-CTES-β-CD/PNIPAM热敏吸附剂具有高吸附能力、抗氧化性、无二次污染等特点，在污水处理方面具有广阔的应用前景。相信这项工作表明了一种提高 MXenes 抗氧化性的新方法。