The use of solution processes to fabricate perovskite solar cells (PSCs) represents a winning strategy to reduce capital expenditure, increase the throughput, and allow for process flexibility needed to adapt PVs to new applications. However, the typical fabrication process for PSC development to date is performed in an inert atmosphere (nitrogen), usually in a glovebox, hampering the industrial scale-up. In this work, we demonstrate, for the first time, the use of double-cation perovskite (forsaking the unstable methylammonium (MA) cation) processed in ambient air by employing potassium-doped graphene oxide (GO-K) as an interlayer, between the mesoporous TiO2 and the perovskite layer and using infrared annealing (IRA). We upscaled the device active area from 0.09 to 16 cm2 by blade coating the perovskite layer, exhibiting power conversion efficiencies (PCEs) of 18.3 and 16.10% for 0.1 and 16 cm2 active area devices, respectively. We demonstrated how the efficiency and stability of MA-free-based perovskite deposition in air have been improved by employing GO-K and IRA.