Photoconductive NiOx hole transport layer for efficient perovskite solar cells

NiOx is widely applied in perovskite solar cells (PSCs) as a hole transport layer. However, its poor conductivity limits the further improvement of device performance. Motivated by photoconductive phenomenon, here we propose a photoconductive NiOx-Pc hole transport layer in PSCs through combining with phthalocyanine (Pc). Under illumination, Pc molecule absorbs light and will be excited. Then photogenerated charges on Pc molecule will transfer to NiOx spontaneously and increase the hole density of NiOx film, thus improving its conductivity. As a result, > 300% increase in conductivity is observed in NiOx-Pc film and its conductivity reaches 4.6 * 10(-4) S m(-1). PSCs with NiOx-Pc exhibit high efficiency of 21.68%, which is much higher than control devices (19.74%). In addition, device stability is also improved in PSCs with NiOx-Pc and over 95%of initial efficiency is retained after 85 degrees C for 800 h.

Automated summary

This study proposes a photoconductive NiOx-Pc hole transport layer in perovskite solar cells (PSCs) by combining with phthalocyanine (Pc) to improve the conductivity of NiOx film. The experimental results show that the conductivity of NiOx-Pc film significantly increases, leading to improved efficiency and stability of PSCs.