MO.3.A || Sustainable Chemicals and Materials

Glogic, Edis; Futsch, Romain; Rougier, Aline; Sonnemann, Guido

Electrochromic devices, ECDs, are used in innovative systems for energy saving (e.g., smart tinting windows) and Internet-of-Things, IoTs. For the later, Electrochromic displays , can support information exchange and autonomy of conventional and novel products while consuming very little energy that can be delivered wirelessly through a smartphone. The environmental performance of these devices can be influenced by a variety of applicable designs, i.e., choices of materials constituting electrodes, electrolyte, electrochromic layer, and substrate. The selection of architectures that are subsequently tested and developed are routinely based on preconceived notions about their potential impact on the environment. However, an early analysis of the environmental impacts of design choices can be used to direct innovation and research in a more optimal direction. In this study, the Life Cycle Assessment methodology is used to test four possible architectures of ECDs printed on flexible paper substrates used for anticounterfeiting applications. The emphasis is on the choices of materials for electrodes: combining silver and carbon electrodes (ECD1), all-indium-tin-oxide (ITO) (ECD2), combining ITO and carbon electrodes (ECD3), and all-carbon (ECD4). The choices of electrode materials influence quantities and materials of the other components of ECD. Preliminary results show the lowest impacts for ECD3 and highest impacts of ECD1, associated with the high impacts of silver ink particularly on toxicity-related impact categories. Impacts of substrate, electrochromic materials, and electrolyte are comparatively small but their relevance varies among the scenarios. According to these findings, the research should be directed on practical validation of ECD3 architecture, although the ECD4 presents an interesting choice from a practical perspective (allows all-printed ECDs with relatively low impacts). Cost analysis is a possible future step in sustainability analysis.