In Situ Fabrication of Integrated Electrode of Perovskite Solar Cells

An integrated electrode has been in situ fabricated on a titanium substrate by a simple thermal oxidation method. The integrated electrodes can replace glass substrates, fluorine-doped tin oxide (FTO), and TiO2 compact and mesoporous layers in conventional perovskite solar cells (PSCs) with bilayer configuration. Under AM1.5 illumination, photon-to-electricity conversion efficiency (PCE) of the fabricated PSCs is 9.92%, which is higher than that of PSCs with bilayer configuration. Interestingly, photoluminescence (PL) measurements show a lower charge recombination in the integrated electrodes than normal TiO2 electrodes fabricated layer by layer, thereby suggesting that photoinduced electrons in integrated electrodes can be more efficiently extracted. We also found that our PSCs have high conductivity and excellent stability. Therefore, the developed technique is suitable for fabricating large area PSCs.