Co(II)-Based Metallo-Supramolecular Polymers

  • Masayoshi HiguchiEmail author
Part of the NIMS Monographs book series (NIMSM)


This chapter introduces synthesis, properties, and device application of Co(II)-based metallo-supramolecular polymer (polyCoL1-5) and the derivatives. Section 4.1 shows synthetic procedure of polyCoL1-5 by the 1:1 complexation of Co(II) ions with bis(terpyridine)s (L1-5). The molecular weight (Mw) of polyCoL1 is determined to be 4.31 × 103 using gel permeation chromatography (GPC) by the addition of a salt to the eluent to prevent decomplexation. The color of the obtained polymers is orange or yellow. Section 4.2 introduces optical and electrochemical properties and yellow electrochromism of the polymers. The electrochromism between yellow and colorless is triggered by the electrochemical redox between Co(II) and Co(III). Section 4.3 describes black electrochromism of polyCoL1, which is caused by the electrochemical reduction from Co(II) to Co(I), upon applying a negative potential in an aqueous solution including an electrolyte. This electrochromic behavior is influenced by pH of the electrolyte solution. Section 4.4 explains Co(III)-based polymer formation via polycondensation of the Co(III) mono complexes. The obtained polymers show nonvolatile memory properties in the device, composed of the polymer film on Si/SiO substrate with Au electrodes (Sect. 4.5). Random access memory (RAM) and read only memory (ROM) properties of the device enable reversible information processing and permanent memory storage capacities.


Co(II)-based metallo-supramolecular polymer Yellow electrochromism Black electrochromism Polycondensation Nonvolatile memory device RAM 


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Copyright information

© National Institute for Materials Science, Japan 2019

Authors and Affiliations

  1. 1.National Institute for Materials ScienceTsukubaJapan

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