Dielectric barrier discharge jet processed TiO2 nanoparticle layer for flexible perovskite solar cells

For attaining good-performance perovskite solar cells (PSCs), the carrier collection from the perovskite material to the transport layer plays a prominent role; herein, we demonstrate an atmospheric pressure plasma treatment technique to enhance the interface properties between the active perovskite layer and electron transport layer (ETL). A scan-mode low-temperature helium dielectric barrier discharge (DBD) jet is applied to process the TiO2 nanoparticle layers for the flexible n-i-p PSCs made on ITO-coated polyethylene naphthalate substrates. When the surface of TiO2 nanoparticle ETL is treated by the DBD jet at a scan rate of 2 cm s(-1) and scan height of 5 cm by ten times, the photoelectrical conversion efficiency of the cell is enhanced from 12.30% to 13.66%. The performance improvement can be attributed to the increase of hydrophilic O-C = O functional groups on the surface of the TiO2 nanoparticle layer and the reduction of charge transfer resistance of the cell revealed by x-ray photoelectron spectroscopy and electrochemical impedance spectroscopy, respectively. The results show that the low-temperature DBD jet treatment is a promising technique for processing flexible photovoltaic devices.

Automated summary

This study demonstrates the use of atmospheric pressure plasma treatment to enhance the interface properties between the active perovskite layer and electron transport layer in flexible perovskite solar cells. By applying a scan-mode low-temperature helium dielectric barrier discharge (DBD) jet to process the TiO2 nanoparticle layers, the photoelectrical conversion efficiency of the cells is improved from 12.30% to 13.66%. This improvement is attributed to the increase of hydrophilic functional groups and the reduction of charge transfer resistance on the surface of the TiO2 nanoparticle layer.