Osaka explained the technology combines a ‘transparent paper’ with high transparency (90% of visible-light transmittance of paper made from cellulose nanofibers) and a conventional ‘white paper’ made from cellulose pulp fibres, which fabricates a highly transparent electrode and a white electrolyte with high visibility.
In EC devices, when voltage is applied to a transparent EC electrode, ions or electrons move into the EC layer in the electrolyte (ionic liquid), resulting in coloration or decolsoration. However, with conventional EC devices, sealing was necessary for preventing leakage of the electrolyte. This meant making thin films was difficult, and EC performance was compromised due to evaporation of the electrolyte.
A group of researchers led by Hirotaka Koga at Oksaka, claim to have succeeded in preparing a paper electrolyte by supporting a non-volatile electrolyte (1-butyl-3-methylimidazolium tetrafluoroborate [bmim]BF4)
