A new alkanethiol derivative containing a 18-crown-6 function (1) was introduced for fabrication of electrode surface. A 1-modified gold electrode was prepared by dipping in the solution of 1. By using a [Fe(CN)6]3-μ redox couple as an electrochemical probe, a densely packed, electrochemically insulating surface layer formation by 1 was confirmed by cyclic voltammetry. This made the amperometric sensory application of the electrode difficult. On the other hand, this property suggested a possible application to chemical sensors with electrical impedance measurements. The idea was successfully demonstrated by sensing gaseous ammonia. Organic gases such as benzene and chloroform did not give response. The surface-immobilized crown ether played a key function in determining the selectivity.
All Science Journal Classification (ASJC) codes
- Analytical Chemistry