Doping of Halide Perovskites

Methylammonium lead Iodide (MAPbI3) based organic-inorganic hybrid perovskites (OIHP) have emerged as promising solar photovoltaic absorbers, with power conversion efficiency increasing from 3.8% to 23.7% in the last 10 years. Such high efficiency combined with low-temperature solution fabrication process make OIHP promising candidates for the next generation of photovoltaic materials. Current solar cell designs use semi-insulating or low carrier density layers coupled to hole and electron transport contact materials. Controlled doping, both n and p-type, would allow for tuning electrical conductivity and fabrication of p-n homojunctions, opening great opportunities in device applications that go beyond solar cells.
In this presentation we discuss possible approaches to doping of MAPbI3, exploring substitutional and interstitial impurities, on both organic and inorganic sites. Using density functional theory and hybrid functional calculations we explore all possible configurations of the various dopants, analysing formation energies, thermodynamic transition levels, and dopant solubilities.