Inkjet-printed platinum counter electrodes for dye-sensitized solar cells

In this study, inkjet printing method was successfully demonstrated to produce catalytic platinum layers for dye-sensitized solar cells. Our work includes meticulous optical, morphological, and electrocatalytical analyses of precisely inkjet-patterned counter electrodes as well as traditionally drop-cast samples. Similar catalytic performance was obtained with both methods (RʹCT = 1.2 Ω cm2 for drop-cast and RʹCT = 1.6 Ω cm2 for inkjet-printed) at same Pt loading (ca. 2.5 μg/cm2), and correspondingly almost same cell efficiencies (ηdrop-cast = 6.5% and ηprinted = 6.7%). All the cells exhibited high stability by keeping their efficiencies after being subjected to a 1000 h aging test under 1 Sun and 35 °C at the open circuit condition. These results highlight the potential of inkjet printing to realize precisely patterned and no-material-wasting counter electrodes by controlled dispensing of the functional solution.