Fabrication and characterization of CH3NH3PbI3 solar cells with added guanidinium and inserted with decaphenylpentasilane

Abstract

Abstract In this work we investigated the effects of the addition of guanidinium [C(NH2)3; GA] on CH3NH3PbI3 perovskite solar cells fabricated at a high temperature of 190°C in atmospheric air. The addition of GA iodide and the insertion of decaphenylpentasilane between the perovskite and hole transport layer improved the external quantum efficiency and short-circuit current density, and the conversion efficiencies were stable after 1 month. X-ray diffraction showed that the lattice constant of the perovskite crystals was increased by the addition of GA, and addition of GA also improved the surface morphology. First-principles calculations on the density of states and band structures showed reduction of the total energy by the addition of GA and the effectiveness of the nitrogen atoms in GA.