Utilization of Cellophane Paper as Flexible Substrates in Perovskite Solar Cells

Perovskite solar cells are the most emerging research area among different modern photovoltaic technologies due to the fast development of efficiency. It has improved from 3.5% to 25.8% in a decade.[1] In addition, advantages of perovskite solar cells include superpower conversion efficiency, low-cost, and solution processability. At this time, paper has become an attractive print material for electronics into a wearable due to its flexibility, inexpensive, lightweight, foldable, recyclable and natural disposables.[2] Cellophane paper is also an interesting option because translucent, light, and affordable. In this work, we are interested in fabrication cellophane paperbased planar perovskite solar cells. Indium tin oxide (ITO) was coated on cellophane paper as a transparent electrode with tin oxide (SnO2, as an electron transport layer), perovskite (as a light absorber), Spiro-MeOTAD (as the hole transport layer), and silver (Ag, as the electrode). The structural architecture was cellophane/ITO/SnO2/perovskite/Spiro-MeOTAD/Ag (Fig. 1). Our discovery contributes an approach to fabricate dependable power source for lightweight electronics in the future.