화학공학소재연구정보센터
Journal of the Electrochemical Society, Vol.144, No.4, 1185-1188, 1997
Enhancement of Electrochemical Performance of Disulfide Using Polyvinylpyridine Film
In light of the possible utilization as a positive electrode material in lithium batteries, an attempt was made to improve the redox characteristics of the organodisulfide cathode (2,5-dimercapto-1,3,4-thiadiazole, DMcT) by trapping it within a basic polymer such as polyvinylpyridine (PVP). An investigation with cyclic voltammetry indicated that the redox process of DMcT on PVP film is enhanced. That is, the redox current increased in both the oxidation and reduction processes. Such an enhanced redox behavior of DMcT may be caused by the basic environment of the PVP matrix Pn which DMcT exists as a thiolate anion that can be oxidized at lower, or favored, overpotentials. In fact, we confirmed by a separate experiment that in a pyridine environment; the standard rate constant which corresponded to the oxidation of DMcT increased by three orders of magnitude compared with thai of the DMcT on a bare basal plane pyrolytic graphite (BPG) electrode. Due to the advantage of electrochemical binding of the thiolate anions to the PVP matrix, it is suggested that DMcT/PVP composite electrode may behave as improved cathode materials in lithium batteries.