All-Printed Roll to Roll Perovskite Photovoltaics Enabled by Solution Processed Carbon Electrode.

Perovskite photovoltaics have shown great promise in device efficiency but also the promise of scalability through solution-processed manufacture. Efforts to scale perovskites have been taken through printable mesoporous scaffolds and slot die coating of flexible substrates roll to roll. However, to date there has been no demonstration of entirely roll to roll coated devices due to the lack of a compatible solution processable back electrode instead high value evaporated metal contacts are employed as a post process. Here in this study, the combination of a low-temperature device structure and roll to roll compatible solution formulations have been employed to make a fully roll to roll printable device architecture overcoming interlayer incompatibilities and recombination losses. Therefore, the n-i-p device structure of SnO 2 /Perovskite/PEDOT/Carbon was employed to form an ohmic contact between a p type semiconductor and printable carbon electrode. In particular, the results show that the small-scale device efficiencies of 13-14% are achieved matching the device performance of evaporated gold electrodes. Also, this entirely roll to roll coated perovskite prototype represents a game changer, reaching over 10% (10.8) stabilised PCE with unencapsulated long-term stability retaining 84% of its original efficiency over 1000 hours under 70% RH and 25°C. This article is protected by copyright. All rights reserved.