新型高柔韧全固态氢离子选择电极的制备与应用

Preparation and Application of a Novel High-flexibility All-solid Hydrogen Ion Selective Electrode

微生物腐蚀现象中有50%是由硫酸盐还原菌(sulfate-reducing bacteria,SRB)引起,pH作为SRB生长过程的重要指标,其准确、实时监测对于腐蚀的研究有重要意义。本研究构建了一种高柔韧性全固态氢离子选择电极,将高柔韧性的银丝作为导电基底,运用电化学沉积技术将氧化石墨烯沉积在银丝上,沉积具有大电容、能进行离子与电子信号转换的固接转换层。将三正十二胺(TDDA)作为中性载体,与四苯基硼酸钾(KTPB)、葵二酸二辛酯(DOS)、聚氯乙烯(PVC)等制备而成的H^+选择性膜包覆在转换层上,获得全固态的氢离子选择电极。测试结果表明,电极的pH响应范围达到2.5~12,响应性能稳定,选择性和抗干扰性优良,在海水、离子种类复杂的培养基中的测试结果与商用pH计吻合度达95%以上。

Sulfate-reducing bacteria(SRB)are a large of microorganisms that use sulfate as terminal electron acceptor for energy generation,they are the most corrosive and widely studied corrosion microorganisms.pH is an important indicator of SRB metabolism,and growth accurate and real-time monitoring is of great significance for the study of corrosion.A flexible all-solid H^+ ion selective electrode was prepared.The flexible silver wires were used as conductive substrates.Reduced graphene was subsequently deposited on silver wires by electrochemical deposition method.The solid contact conversion layer with a large capacitance was used for signal conversion between ions and electrons.Finally,the graphene layer was coated by a neutral carrier membrane.The neutral carrier membrane contained tri-n-dodecylamine(TDDA),potassium tetraphenylborate(KTPB),dioctyl sebacate(DOS),and polyvinyl chloride(PVC).The novel H^+ selective electrode held excellent stability after 7 days and strong anti-interference ability.Selective electrode responded quickly to concentration change of H^+ and a liner response was obtained in the range of 2.5~12.Additionally,the use of commerce pH meters verified the accuracy of novel H^+ selective electrode by measuring three kinds of artificial samples,the results indicated that the accuracy of H^+ selective electrodes was greater than 95%.