Viologen-functionalized biomass-based furan trimer as a multi-coloring electrochromic material

Abstract

The ability of electrochromic devices (ECD) to undergo a reversible color change when exposed to different voltage conditions has rendered them suitable for applications in smart mirrors, energy-efficient windows, and multi-color displays. While most of the compounds used for ECD fabrication are inorganic metal oxides, various studies have demonstrated that organic materials can also be promising candidates for ECD applications. Recently, our research group introduced a trifuran oligomer that can undergo reversible colorations at lower voltage ranges. However, the decoloration ability of the compound for a better color transition upon reduction remains a challenge. In this study, we successfully synthesized a viologen-functionalized biomass-based trimer and explored its electrochromic properties. Based on our findings, the novel compound exhibited a red to transmissive yellow to deep blue multi-coloring ability when it undergoes oxidation and reduction by virtue of its electrochromic components. Additionally, the introduction of viologen to the structure of the trifuran moiety enhanced the decoloration capacity of the ECD, therefore rendering the color transitions more visible.