Effects of halogens and alkali metals on guanidinium-ethylammonium hybrid-doped perovskite photovoltaic devices

Abstract

Effects of substitution of halogen anions and addition of alkali metal cations for guanidinium (GA)-ethylammonium (EA) hybrid-doped perovskite solar cells were investigated by fabricating devices and comparing their photovoltaic properties. The halogen compositions of the additives were found to contribute to the improvement of preferred orientations of perovskite crystals, and the order of the effectiveness was I, Cl, and Br. In addition, the addition of alkali metal cations contributed to improvement of the conversion efficiencies, and 3 % addition of cesium at the CH3NH3 site was the most effective. It was also found that the short-circuit current densities and fill factors depended on the (100) preferred crystal orientation of the perovskite compounds.

Keywords

• Perovskite
• Structure
• Guanidinium
• Ethylammonium
• Halogen
• Cesium