Proceedings of International Conference on Hybrid and Organic Photovoltaics (HOPV19)
Publication date: 6th February 2020
Enhanced performance of MAPbI3 based solar cell upon addition of p-type molecular dopant
Bosky Sharma1, Parag Bhargava, 1, 2* and Dinesh Kabra1, 3*
1Centre for Research in Nano-Technology and Science, Indian Institute of Technology Bombay, India- 400076.
2Department of Metallurgical Engineering and Material Science, Indian Institute of Technology Bombay, India- 400076.
3Department of Physics, Indian Institute of Technology Bombay, India- 400076.
Abstract
Halide perovskite are known to have defects at grain boundaries and at interfaces and there are continuous efforts in community to overcome them by various passivation techniques, like use of various n-type small organic molecule as additive, solvent additive, mixing of larger cation to decorate the grain boundary at interfaces with quasi-2D perovskites. However, we employ an additive-engineering strategy of molecular doping to passivate bulk defects by introducing a p-type organic molecule in CH3NH3PbI3 (MAPbI3) absorber layer of perovskite thin film based solar cell to enhance its performance. It passivates bulk defects which results in reduced non- radiative carrier recombination, improved charge separation, restrained leakage current with better structural and morphological quality of MAPbI3 film. The power conversion efficiency (PCE) increased from ~9% to ~15% with an optimized ratio of p-type dopant. A reduced J-V hysteresis was simultaneously exhibited by the perovskite solar cell with a planar structure of ITO/PEDOT: PSS/perovskite film/PCBM/BCP/Ag. These enhanced performances are attributed to compact surface coverage, large shunt resistance and improved charge transport. These results were found to be in accordance with steady-state and transient photoluminescence studies, where an improved photoluminescence is observed by using MAPbI3 solution with dopant. The study suggests that small organic molecule plays an important role in passivation and improving MAPbI3 film quality. It results in enhanced photovoltaic and opto-electronic performance. It leads to an approach towards utilizing other p-type additives for enhancing perovskite solar cell performance as well as other photoelectric devices.
NCPRE,IRCC IIT Bombay