Refilling DSSCs as a method to ensure longevity

Dye-sensitized solar cells can be prepared from non-toxic and inexpensive materials outside a cleanroom and are thus of utmost interest for utilization of different substrates, amongst others on textile fabrics. Since the electrolyte in such cells is usually fluid and the alternatives are mostly toxic, expensive or too rigid to be included in a textile fabric, drying-out of the electrolyte is an urgent problem which must be taken into account. In this study the influence of refilling the electrolyte in different time intervals is investigated, showing that in this way the power reduction with time can be stopped for at least four months. Variations of the maximum power with time depend additionally on the dye used for the cells, showing the least time-dependence for black beans and maqui berry powder, while cells with black rice, exhibiting the largest power after preparation, suffered a severe power drop during this time which could not completely be counteracted by refilling the electrolyte. (C) 2018 Elsevier GmbH. All rights reserved.