Rapid, low-temperature, air plasma sintering of mesoporous titania electron transporting layers in perovskite solar cells

Reducing the sintering temperature and time of mesoporous titanium dioxide (m-TiO2) from the standard thermal approach of baking at 500degree celsius for 1 h is an important step for employment of mesoscopic perovskite solar cells (PSCs). We present a robust method based on atmospheric pressure ambient air plasma of the diffuse coplanar surface barrier discharge (DCSBD) for sintering of m-TiO2 in 2.5 min at 70 degree celsius. When implemented in PSCs as an electron transport layer an efficiency of (15.8 +/- 1.0) % was achieved, which is on the same level as a standard thermal approach. The organic moieties which hinder the perovskite infiltration into the porous structure were removed to a similar extent as the thermal sintering. The approach does not affect the conduction band alignment with the perovskite absorber and an appropriate energy offset is preserved.

Automated summary

Reducing the sintering temperature and time of mesoporous titanium dioxide is crucial for the application of mesoscopic perovskite solar cells. In this study, a plasma-based method was developed to sinter the mesoporous titanium dioxide in a significantly shorter time and lower temperature compared to the standard thermal approach. The efficiency achieved using this method was comparable to the standard thermal approach.