钴氰化钠与铁氰化钠结构类似，而其在固/液界面上的电子转移特性却并不显著. 使用扫描电化学显微镜（SECM）构建了fL~pL体积的电化学微体系. 在微体系中溶剂蒸发，电解质则会浓缩结晶. 当电活性物质与支持电解质的晶格参数匹配时，二者可发生共结晶形成固体溶液. 本文采用该方法制得钴氰化钠/氯化钠固体溶液微晶体，结合微加工技术构建了固体电极/固体溶液界面，该钴氰化钠在固体溶液中即有很好的电子转移特性.
Although the molecular structures are similar to each other, the redox property of Co(CN)63- at solid/liquid interface is not so good as Fe(CN)63-. 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)63- replaced the sites of NaCl65- 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.
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