均一沈殿法による固体膜型コバルト(II)イオンセンサー(物質生命化学科)

Abstract

In order to examine the response characteristics of a cobalt (II) ion-sensor (Co(II)-ISE) with a solid-state sulfide membrane, several kinds of mixed sulfidis of silver and cobalt were prepared by different methods. Consequently, Co (II)-ISE fabricated by fine particles Ag_2S and CoS powders (ca. 1μm diameter) formed from homogeneous precipitation showed a much better response than those of other methods. The Ag_2S and CoS particles were synthesized from a mixed solution of thioacetamide with and without urea, silver nitrate and cobalt nitrate, respectively, at 70℃ over 2h period. The electrode showed a near-Nernstian response to Co^<2+> in the concentration range from 10^<-4> and 10^<-1> mol/l, and found to have several fairly well such as short response time, reproducible potential stability and life-time. It was assumed that fine Ag_2S and CoS particles prepared by homogenious precipitation method could play an important role in the performance of such an electrode.