从半导体刻蚀废气中吸附分离NF3具有重要的工业应用价值.通过在多孔有机分子笼(cage-like organic network,CON)中引入碘离子,制得了高NF3吸附选择性的离子型吸附剂(I-CON).DFT理论计算表明,碘离子的引入在吸附剂孔道表面形成了离子化的电场环境,使被吸附的NF3分子发生诱导极化,因此增强了材料对NF3的吸附能力.单组分气体吸附测试结果表明,相较于CON,I-CON对NF3 的吸附容量从30.49mL/g提高到45.13mL/g,理想吸附溶液理论选择性从10.59~15.49提高到15.01~19.47;在穿透曲线测试中,I-CON也比CON表现出更强的NF3动态吸附能力.以上结果证实了离子改性能够增强材料对NF3的吸附分离性能,为分离与回收NF3提供了技术参考.
Adsorptive separation of NF3 from semiconductor exhaust gases has become an increasingly important topic in industrial applications.By introducing iodine ions into cage-like organic network(CON),quaternized I-CON material was prepared.The DFT calculation revealed that the electric field was formed on the pore surface by introducing iodide ions,which enhanced the inducing force between NF3 molecule and I-CON framework.Compared with CON,the NF3 adsorption capacity of I-CON increased from 30.49mL/g to 45.13mL/g and the IAST selectivity increased from 10.59-15.49 to 15.01-19.47 according to the single-component gas adsorption results.Moreover,the dynamic adsorption selectivity of I-CON was also higher than that of CON in the breakthrough tests.Thus,separation ability of CON could be effectively improved by ion modification,showing its potential for the real-world NF3 capture and enrichment.