关键词: 固体溶液, 固/固界面, 电化学微体系, 扫描电化学显微镜

Abstract: Although the molecular structures are similar to each other, the redox property of Co(CN)₆^3- at solid/liquid interface is not so good as Fe(CN)₆^3-. In this paper, scanning electrochemical microscopy (SECM) was adopted to construct an electrochemical microsystem with a volume of fL~pL, in which a micropipette with micrometer-sized orifice was employed as the scanning tip. Due to the evaporation of water, the NaCl electrolyte is concentrated to form a microcrystal. During the crystallization, the redox species Co(CN)₆^3- replaced the sites of NaCl₆^5- unit due to their matching lattice parameters, i.e., the solid solution. Single Na₃Co(CN)₆/NaCl microcrystal was assembled in-situ between a pair of gold microelectrodes on a microchip to construct the solid/solid interface, which was found to have good voltammetric behavior.

Key words: solid solution, solid/solid interface, electrochemical microsystem, scanning electrochemical microscopy