Abstract:
Zirconium-based metal-organic frameworks (Zr-MOFs) have been considered as prospective materials for the degradation of nerve chemical warfare agents (CWAs) but show poor catalytic performance toward blister agents. Moreover, the powder issues and the poor adsorption capability also remain as the major challenges for the application of Zr-MOFs in practical CWA detoxification. Herein, a series of defected granular UiO-66-NH2 metal-organic gels are synthesized via adjusting the amount of added concentrated hydrochloric acid for the decontamination of 2-chloroethyl ethyl sulfide (2-CEES), a sulfur mustard simulant. The half-life of 2-CEES decontaminated by defected granular UiO-66-NH2 metal-organic gels can be shortened to 7.6 min, which is the highest reported value for MOFs under ambient conditions. The mechanism of decontamination is that the amino group on the linkers in UiO-66-NH2 MOGs undergoes a substitution reaction with 2-CEES to yield 2-(2-(ethylthio)ethylamino)terephthalic acid, which is less toxic and fixed in the frameworks. The recycling test corroborates that the granular UiO-66-NH2 xerogels possess good stability and reusability. Static adsorption and desorption tests show that UiO-66-NH2 xerogels possess a high 2-CEES vapor adsorption capacity of 802 mg/g after exposure for 1 d and only 28 wt % desorption capacity after air exposure for 7 d. The dual function of ultrafast degradation and high adsorption capability provide a firm foundation for using UiO-66-NH2 xerogels as a future protection media.
摘要:
锆基金属有机骨架(Zr-MOF)已被认为是降解神经化学战剂(CWAs)的潜在材料,但对起泡剂的催化性能较差。此外,粉末问题和差的吸附能力也仍然是Zr-MOFs在实际CWA解毒中应用的主要挑战。在这里,通过调整2-氯乙基乙基硫醚(2-CEES)的浓盐酸的加入量,合成了一系列有缺陷的颗粒状UiO-66-NH2金属-有机凝胶,硫磺芥末模拟物。由缺陷颗粒UiO-66-NH2金属有机凝胶净化的2-CEES的半衰期可以缩短至7.6分钟,这是环境条件下MOFs的最高报告值。去污机理是UiO-66-NH2MOGs中连接子上的氨基与2-CEES进行取代反应,生成2-(2-(乙基硫基)乙基氨基)对苯二甲酸,毒性较小,固定在框架中。回收试验证实颗粒状UiO-66-NH2干凝胶具有良好的稳定性和可重复使用性。静态吸附和解吸测试表明,UiO-66-NH2干凝胶在暴露1d后具有802mg/g的高2-CEES蒸气吸附能力,在空气暴露7d后仅具有28wt%的解吸能力。超快降解和高吸附能力的双重功能为使用UiO-66-NH2干凝胶作为未来的保护介质提供了坚实的基础。