电控离子交换技术(electrochemically switched ion exchange,ESIX)是将电活性离子交换材料(EXIMs)沉积或涂覆在导电基底上,通过电化学控制导电基底上活性材料氧化还原状态实现目标离子置入与释放,从而实现离子的分离。该技术具有痕量...电控离子交换技术(electrochemically switched ion exchange,ESIX)是将电活性离子交换材料(EXIMs)沉积或涂覆在导电基底上,通过电化学控制导电基底上活性材料氧化还原状态实现目标离子置入与释放,从而实现离子的分离。该技术具有痕量提取、无二次污染、速率可控、高选择性等优点。通过共沉淀法制备Ni Fe Mn LDH,并将其与碳纳米管(CNTs)、聚偏二氟乙烯(PVDF)混合涂覆到石墨板上,制得NiFeMn LDH/CNTs/PVDF膜电极。NiFeMn LDH层板上具有丰富的羟基官能团,可与W(Ⅵ)发生羟基配位;层间的阴离子与W(Ⅵ)进行离子交换,可为W(Ⅵ)提供丰富的活性位点。在ESIX系统中,膜电极对W(Ⅵ)的吸附容量可达122.10 mg·g^(-1),且W(Ⅵ)与Mo(Ⅵ)、Cl^(-)、■分离因子(■)分别为1.25、19.60、35.80,实现了W(Ⅵ)选择性分离。此外,该膜电极具有优异的循环稳定性,为钨的高效分离提供了新的方向。展开更多
A new solid-state mercury ion-selective electrode was prepared by directly coating the surface of a glassy carbon electrode with tetrahydrofuran solution containing PVC, 25,27-dihydroxy-26,28- bis[(1′-naphthalene) se...A new solid-state mercury ion-selective electrode was prepared by directly coating the surface of a glassy carbon electrode with tetrahydrofuran solution containing PVC, 25,27-dihydroxy-26,28- bis[(1′-naphthalene) selenopropoxy] calix[4]arene, dioctyl phthalate and potassium tetrakis(4-chlorophenyl) borate. The response of the electrode is linear with a good Nernstian slope of 31.5 mV/decade over an Hg 2+ ion concentration range of 5.0×10 -9—5.0×10 -2 mol/L and a detection limit of 1.0×10 -9 mol/L. The response time to achieve a 95% steady potential for Hg 2+ detection is less than 30 s, and the electrode is suitable for use within the pH range of 2—4. The selectivity for Hg 2+ relative to several alkali, alkaline earth, transition and heavy metal ions is good. The mechanism of the potential response of this system was also discussed.展开更多
文摘电控离子交换技术(electrochemically switched ion exchange,ESIX)是将电活性离子交换材料(EXIMs)沉积或涂覆在导电基底上,通过电化学控制导电基底上活性材料氧化还原状态实现目标离子置入与释放,从而实现离子的分离。该技术具有痕量提取、无二次污染、速率可控、高选择性等优点。通过共沉淀法制备Ni Fe Mn LDH,并将其与碳纳米管(CNTs)、聚偏二氟乙烯(PVDF)混合涂覆到石墨板上,制得NiFeMn LDH/CNTs/PVDF膜电极。NiFeMn LDH层板上具有丰富的羟基官能团,可与W(Ⅵ)发生羟基配位;层间的阴离子与W(Ⅵ)进行离子交换,可为W(Ⅵ)提供丰富的活性位点。在ESIX系统中,膜电极对W(Ⅵ)的吸附容量可达122.10 mg·g^(-1),且W(Ⅵ)与Mo(Ⅵ)、Cl^(-)、■分离因子(■)分别为1.25、19.60、35.80,实现了W(Ⅵ)选择性分离。此外,该膜电极具有优异的循环稳定性,为钨的高效分离提供了新的方向。
文摘A new solid-state mercury ion-selective electrode was prepared by directly coating the surface of a glassy carbon electrode with tetrahydrofuran solution containing PVC, 25,27-dihydroxy-26,28- bis[(1′-naphthalene) selenopropoxy] calix[4]arene, dioctyl phthalate and potassium tetrakis(4-chlorophenyl) borate. The response of the electrode is linear with a good Nernstian slope of 31.5 mV/decade over an Hg 2+ ion concentration range of 5.0×10 -9—5.0×10 -2 mol/L and a detection limit of 1.0×10 -9 mol/L. The response time to achieve a 95% steady potential for Hg 2+ detection is less than 30 s, and the electrode is suitable for use within the pH range of 2—4. The selectivity for Hg 2+ relative to several alkali, alkaline earth, transition and heavy metal ions is good. The mechanism of the potential response of this system was also discussed.
