Dye-sensitized solar cells on glass paper: TCO-free highly bendable dye-sensitized solar cells inspired by the traditional Korean door structure

Dye-sensitized solar cells (DSSCs) are considered a suitable photovoltaic system for urban applications and highly bendable DSSCs can be expanded to applications such as dispensable DSSCs for commercial advertising and small portable power sources. However, although many reports have shown flexible or highly bendable photoelectrodes using TCO-coated polymeric substrates or metal meshes, until now, few have shown highly bendable DSSCs using electrodes because the flexibility of a single electrode is not a critical issue for highly bendable DSSCs. Here, we report a new DSSC design, inspired by the traditional Korean door structure consisting of a paper-bonded wooden frame, and a process for TCO-free highly bendable DSSCs utilizing glass paper and metal mesh. In the new DSSC design, constituents such as stainless steel mesh and mesoporous TiO2 loaded with a Ru-complex dye were bonded on the glass paper, which was sputter-coated with Pt on one side and filled with electrolyte. The glass-paper-based flexible DSSCs showed 2% energy-conversion efficiency, which was maintained under bending until the radius of curvature reached 2 cm. The new glass-paper-based flexible DSSCs may have potential applications as low-cost highly bendable solar cells to overcome the limitations of conventional sandwich-type DSSCs.