Abstract
Photovoltaic performances of CsPbI(2)Br solar cells are still lower than those of hybrid inorganic-organic perovskite solar cells, and researchers are exploring ways to improve their efficiencies. Due to its higher thermal stability in comparison with the generally studied hybrid inorganic-organic perovskites, all-inorganic CsPbI(2)Br has recently attracted great attention. By utilizing the combination of MnCl(2) and ZnCl(2) particles doping to modulate film growth, it is found that MnCl(2) and ZnCl(2) particles infiltrate into the holes of the CsPbI(2)Br lattice through the growth procedure, leading to suppressed nucleation and reduced growth rate. The combination assists to achieve higher CsPbI(2)Br crystalline grains for increased J(sc) as high as 15.66 mA cm(-2) and FF as large as 73.37%. It is indicated that a specific combination of ZnCl(2)-MnCl(2) doping can fundamentally improve the film surface morphology, reduce trap density, and suppress the recombination of carriers. Consequently, power conversion efficiency (PCE) is significantly improved from 13.47 to 14.15% compared with the reference device without doping.