The electronic, optical and transport properties, and photovoltaic performances of tetragonal CH3NH3PbI3 with various Sr substitutions for Pb (3.12%, 6.25%, 12.5% and 25%) have been systematically investigated using the first principles method. It is discovered that the 25% Sr content not only reduces the band gap by over 10% to harvest the near-infrared phonons, but also substantially promotes the charge transport through lowering the carrier effective mass and enhancing the carrier mobility. Simultaneously, CH3NH3Pb0·75Sr0·25I3 is conservatively estimated to have a power conversion efficiency of about 19%, showing the improved photovoltaic performance. Further, the phonon-dispersion and formation-energy calculations reveal that CH3NH3Pb0·75Sr0·25I3 is of high dynamic and structural stabilities. The overall improvements in optoelectronics and photovoltaics make CH3NH3Pb0·75Sr0·25I3 promising as an effective optical absorber of solar cells. In contrast, the influences of lower Sr contents are slight. This work provides a theoretical perspective in optimizing the optoelectronic and photovoltaic applications of CH3NH3PbI3.
- Electronic properties
- Sr doping
- Tetragonal CHNHPbI
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Electrical and Electronic Engineering