Solid polymer electrolytes based on gellan gum and ionic liquid for sustainable electrochromic devices

• Autor(a) principal: Alves, R.
• Data de Publicação: 2022
• Outros Autores: Fidalgo-Marijuan, A., Campos-Arias, L., Gonçalves, R., Silva, Maria Manuela, Del Campo, F. J., Costa, Carlos Miguel Silva, Lanceros-Méndez, S.
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: https://hdl.handle.net/1822/82086
• topic: Solid polymer electrolytes; Gellan gum; Ionic liquid; Electrochromic devices; Sustainability; Science & Technology

Materials sustainability is becoming increasingly relevant in every developed technology and, consequently, environmentally friendly solid polymer electrolytes (SPEs) based on gellan gum and different quantities of ionic liquid (IL) 1- Ethyl-3-methyl-imidazolium-thiocyanate [Emim][SCN] have been prepared and applied in electrochromic devices (ECDs). The addition of the IL does not affect the crystalline phase of gellan gum and the samples show a compact morphology, surface uniformity, no phase separation and good distribution of the IL within the carrageenan matrix. The developed SPE are thermally stable up to ~ 100 ºC and show suitable mechanical properties. The most concentrated sample (39 wt.% IL content) reaches a maximum ionic conductivity value of 6.010–3 S cm–1 and 1.810–2 S cm–1 at 30 ºC and 90 ºC, respectively. The electrochromic device (ECD) was fabricated with poly(3,4- ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) as working electrode and the developed SPE was compared with an aqueous 0.1 M KNO3 solution. The electrochromic performance of the electrolyte was assessed in terms of spectroelectrochemistry, demonstrating a fully flexible ECD operating at voltages below 1.0 V. This novel electrolyte opens the door to the preparation of high performance sustainable ECD.