Efficient CH3NH3PbI3 perovskite solar cells based on graphdiyne (GD)-modified P3HT Hole-transporting material

Abstract

Novel large π-conjugated carbon material, graphdiyne (GD), as a dopant to poly(3-hexylthiophene) (P3HT) hole-transporting material (HTM) layer, is introduced into perovskite solar cells for the first time. Raman spectroscopy and ultraviolet photoelectron spectroscopy measurements reveal that relatively strong π-π stacking interaction occurs between GD particles and P3HT (so-called P3HT/GD composite HTM), favorable for the hole transportation and improvement of the cell performance. On the other hand, some GD aggregates exhibit a scattering nature, and thus help to increase the light absorption of the perovskite solar cells in the long wavelength range. As high as 14.58% light-to-electricity conversion efficiency is achieved, superior to the pristine P3HT-based devices. Additionally, the devices exhibit good stability and reproducibility. Time-resolved photoluminescence decay measurements reveal that the P3HT/GD HTM can accelerate the hole extraction compared with pristine P3HT. A novel large π-conjugated carbon material, graphdiyne (GD), is introduced into perovskite solar cells for the first time. As a dopant to poly(3-hexylthiophene) (P3HT) hole-transporting material, GD exhibits relatively strong π-π stacking interaction with P3HT, yielding a high power conversion efficiency value of 14.58% with good stability and reproducibility, superior to the pristine P3HT-based devices.